18' Axles *DO* Fail - Replace Yours ASAP

[Diesel_Aggie]

I have a 1983 Sunrader 18' with the 5-lug axle. I wasn't too worried about it as it seems the 18' models were not subject to the recall and the previous owners had replaced the bearings. Today I needed to use the Sunrader to commute to work as a backup vehicle. At 65mph on I-40 the left rear duals decided they no longer wanted to be attached to the rest of the vehicle. There was no warning. Controlling a Sunrader while riding on the brakes shoes/backing plate is a major challenge. I was very lucky and was able to slide to the shoulder without losing control and rolling. It set up a severe fishtail that was hard to control. It seems the fiberglass survived with no damage. I still need to make a close inspection of the wheelwell area. I'd highly encourage anyone with the 5 lug set up to replace it ASAP.

If anyone has put the '87 up DRW axle in a 1979-1983 Toyota RV please contact me. I'm still not sure how the later model rear end attaches to the older body style. Is fabrication required? I know Toyota supplied the conversion kits to the RV manufacturers that included the proper brackets for each body style. I am unable to find valid part numbers for this kit or bracketry. I assume I need to get the springs along with the axle and wheels? Thanks.

On edit I'd like to add that mileage is 99,000 and I've never had more than 200 pounds inside since I've owned it.

Edited May 21, 2008 by Diesel_Aggie

[Yostfmx]

WOW! thats crazy man!!! I have a 18'' sunrader that I plan on using the 5 lug on. Take some pictures of the wheel/motorhome and post them up here.

[shandamac]

DA,

So glad you weren't seriously injured. I can only imagine that it was an horrific thing to go through. I'm taking your warning to heart. I'm a new owner of an 81 rader, and I am also concerned about it's 5 lug duals, even though the previous owner said that they'd had the rear axle changed out from a 3/4 to 1 ton in 2001. It's still got those 5 lugs.

Wishing you and your rader a speedy recovery.

ShandaMac

[Yostfmx]

Shandamac, thats enough to scare us uh...

[loub213]

My son, who is an OTR driver, was headed west bound on I-40 in Amarillo & called me when he saw you. He saw the dualies traveling all by themselves first, he said a good mile before he saw you. He called me at 7:37pm. Good luck to you.

Lou

[turtle]

If anyone has put the '87 up DRW axle in a 1979-1983 Toyota RV please contact me. I'm still not sure how the later model rear end attaches to the older body style. Is fabrication required? I know Toyota supplied the conversion kits to the RV manufacturers that included the proper brackets for each body style. I am unable to find valid part numbers for this kit or bracketry. I assume I need to get the springs along with the axle and wheels? Thanks.

I replaced the axle in my 17 foot 1981 diesel about 14 years ago with one out of a salvaged 1986 truck.

If you get an axle out of a 1986 -1988 model you can use the springs from the salvage yard truck. From 1989 and later the springs are wider and it will take more fabrication.

Look under your coach. If the shocks go from the mounts directly up to the frame cross member like this / \ you will need to do some thinking as the later 1 ton axles have shocks that go before and after the axle to the actual frame not the cross member as in this photo of my conversion:

http://www.toymike.com/diesel/pics/dieselUnder.jpg

I ordered upper shock mounts for a 1988 4x4 from the dealer and welded them onto the frame to use the more modern shock mouthing system that came with the springs I got from the salvage yard along with the axle. If you go this route measure the distance between the spring clamps and new upper mounts so that you can get a shock that is long enough for this new application. I went with Bilstein 4x4 lift models to get the lenght I needed.

Some early 1986 1 ton rear axles have left hand threads on the drivers side (just a word of caution...) Toyota abandoned this OTR truck stud system the year the 1 ton came out but keep this in mind if you get an early 1986 axle. Left had thread lug nuts are still available from the dealer but tire monkeys will have a tendency to spin off the studs if you do not tell them about the left threads.

Start calling salvage yards close to you. These axles are out there, you just have to look for them.

Make sure you get an axle with 4.10:1 gearing. You do not want 3.90:1 gearing. I replaced the ring and pinion in my donor axle with 4:56:1 gearing and am VERY happy with the improved performance.

[turtle]

I am also concerned about it's 5 lug duals, even though the previous owner said that they'd had the rear axle changed out from a 3/4 to 1 ton in 2001. It's still got those 5 lugs.

The owner was mistaken, misrepresenting, or misinformed by the shop that did the repair on yours.

Your axle is still a 1/2 ton and prone to wheel loss.

Toyota did make some 1 ton 5 lug axles but they do not look like yours. They have full inner and outer bearings just like the 6 lug axles.

Your axle is a single bearing 1/2 ton axle.

[TheLittlePuppy]

The guy we bought our '84 Toyota Dolphin from was a mechanic and he replaced the rear axle with a heavy-duty one however it still has 5 lugs not 6. Our Toyota mechanic says this axle is okay, but I'm not convinced especially after reading everything here. Are these full-floating 6 lug rear axles hard to find and what else do we need besides that? What will this cost (estimate)? Thanks for any info on this.

Charles & Dianne

[turtle]

The guy we bought our '84 Toyota Dolphin from was a mechanic and he replaced the rear axle with a heavy-duty one however it still has 5 lugs not 6. Our Toyota mechanic says this axle is okay, but I'm not convinced especially after reading everything here. Are these full-floating 6 lug rear axles hard to find and what else do we need besides that? What will this cost (estimate)? Thanks for any info on this.

Charles & Dianne

Toyota did make some 1 ton 5 lug axles. They are VERY uncommon but they do exist. Do you still have a Toyota axle in the coach?

Without seeing a photo of what your axle looks like it would be imposable to tell whether you have a stock 1/2 ton axle or an early 5 lug 1 ton axle.

The common 1 ton full floating axle can be found in salvage yards and will cost you anywhere between $500 and a up depending on how they feel when they are pricing it to you (don't look desperate)....

You did not say where you were located so it is hard to point you somewhere.

Axle replacements are rather straight forward and can be done in a day so figure your shop hours x hourly rate to get an idea unless you want to do it yourself. Dealing with a suspension place or speed shop would be your best bet rather than a general shop as they are more accustomed to doing axle replacements.

You will also need to get 6 lug rims with the axle. Tires are the same size so can be xfered from your old rims to the new rims if they are still good (i.e. not too old)

[TheLittlePuppy]

Toyota did make some 1 ton 5 lug axles. They are VERY uncommon but they do exist. Do you still have a Toyota axle in the coach?

Without seeing a photo of what your axle looks like it would be imposable to tell whether you have a stock 1/2 ton axle or an early 5 lug 1 ton axle.

The common 1 ton full floating axle can be found in salvage yards and will cost you anywhere between $500 and a up depending on how they feel when they are pricing it to you (don't look desperate)....

You did not say where you were located so it is hard to point you somewhere.

Axle replacements are rather straight forward and can be done in a day so figure your shop hours x hourly rate to get an idea unless you want to do it yourself. Dealing with a suspension place or speed shop would be your best bet rather than a general shop as they are more accustomed to doing axle replacements.

You will also need to get 6 lug rims with the axle. Tires are the same size so can be xfered from your old rims to the new rims if they are still good (i.e. not too old)

Thanks, Diesel Mike. I don't think it is a Toyota axle, probably just a heavy-duty axle he used. We're in Tulsa, Oklahoma and believe me, when we ask about this we will not use our "we are desperate look"! I just have this sick feeling in the pit of my stomach when reading about wheels coming off as one is driving anywhere over 10 mph. Are the 6 lug rims readily available? We just had new tires put on.

This is such a great site and you all are so helpful!

Dianne

[Rich Carl]

Hi Greg, Diesel Mike, All. Rich Carl here. I visit only occassionally but thought I'd add to this thread.

On your failed 5-lug axle, am very happy to hear you're OK and neither you nor other drivers were injured. Sad to add that your experience mirrors many other ToyRV owners of 5-lug axles. The recall on the undersized 1/2 ton truck axles really was necessary to resolve this very real safety problem.

Turns out I am presently converting a 1983 21' Sunrader to have a rebuilt one ton, 6 lug, full floating rear axle. This is my 2nd axle-swap project, I don't look forward to doing another conversion, so I have for sale another full-floater, set of shock mount plates, and 4 matching 14" dually wheels.

If you intend to do the conversion yourself, it's frankly a tough job needing some parts fabrication and some special-order parts. You should research the whole conversion project before starting, and gather all the parts and have plenty of time and a work space conducive to a long-term project. In addition to what my buddy Diesel Mike has advised, and in random order, you'll need:

- a known-good one ton full floating axle (then have it rebuilt with new bearings, races, oil seals, brake pads, possibly wheel cylinders, and certainly have the drums resurfaced);

- a pair of used 2WD (-not- the 4WD version) one ton axle shock mount plates (Toyota calls them spring seats; note Toyota no longer sells the OEM part so you must locate some from a donor truck) that you'll have to modify since the shock mount pin geometry will be different;

- new U-bolts fitting the larger diameter one ton axle (plus new washers and heavy duty nuts);

- new rear shocks (Bilstein are best IMO);

- 2 new brake lines plus the single flexible brake hose which is likely a special order;

- new bushings for the sway bar, sway bar link ends, shock mount pins, leaf springs' front and rear shackles;

- weld on new sway bar mounting bracket plates;

- drill out 2 holes to bolt together the drive shaft flange to the rear end's companion flange;

- refill with gear oil appropriate for your climate;

- possibly upgrade your leaf springs depending on size and whether you have airbag suspension;

- this was an off-the-top-of-the-head review and you'll face lots of other challenges.

I wouldn't begin the job until you have all your parts and field service manual diagrams to help.

Kind regards,

Rich

[TheLittlePuppy]

Hi Greg, Diesel Mike, All. Rich Carl here. I visit only occassionally but thought I'd add to this thread.

On your failed 5-lug axle, am very happy to hear you're OK and neither you nor other drivers were injured. Sad to add that your experience mirrors many other ToyRV owners of 5-lug axles. The recall on the undersized 1/2 ton truck axles really was necessary to resolve this very real safety problem.

Turns out I am presently converting a 1983 21' Sunrader to have a rebuilt one ton, 6 lug, full floating rear axle. This is my 2nd axle-swap project, I don't look forward to doing another conversion, so I have for sale another full-floater, set of shock mount plates, and 4 matching 14" dually wheels.

If you intend to do the conversion yourself, it's frankly a tough job needing some parts fabrication and some special-order parts. You should research the whole conversion project before starting, and gather all the parts and have plenty of time and a work space conducive to a long-term project. In addition to what my buddy Diesel Mike has advised, and in random order, you'll need:

- a known-good one ton full floating axle (then have it rebuilt with new bearings, races, oil seals, brake pads, possibly wheel cylinders, and certainly have the drums resurfaced);

- a pair of used 2WD (-not- the 4WD version) one ton axle shock mount plates (Toyota calls them spring seats; note Toyota no longer sells the OEM part so you must locate some from a donor truck) that you'll have to modify since the shock mount pin geometry will be different;

- new U-bolts fitting the larger diameter one ton axle (plus new washers and heavy duty nuts);

- new rear shocks (Bilstein are best IMO);

- 2 new brake lines plus the single flexible brake hose which is likely a special order;

- new bushings for the sway bar, sway bar link ends, shock mount pins, leaf springs' front and rear shackles;

- weld on new sway bar mounting bracket plates;

- drill out 2 holes to bolt together the drive shaft flange to the rear end's companion flange;

- refill with gear oil appropriate for your climate;

- possibly upgrade your leaf springs depending on size and whether you have airbag suspension;

- this was an off-the-top-of-the-head review and you'll face lots of other challenges.

I wouldn't begin the job until you have all your parts and field service manual diagrams to help.

Kind regards,

Rich

Hi Rich,

Thanks for all the information. We will have to have someone do this job for us as we are not mechanically gifted in any way. You've given us a list that we can use and not appear to be totally unknowledgeable on this. I was reading the listing about our little Toy when we bought it last fall and the guy installed a heavy-duty rear axle with heavy-duty bearings. We will try to call him and ask if he used a Toyota axle, so will have to wait for this info. It doesn't sound like it takes forever to have this done so that's good. Again, thanks for the list.

Happy Axle-ing!

Dianne

[motoyhomme]

Here is a picture I pulled from the files on this forum. It is a picture of all of the components in the upgrade kit that Toyota provided to the owners way back when. These kits are no longer provided by Toyota. It does give an idea of what is involved as far as parts go.

Allen

[ChairmanMeow7]

Glad to hear no one was seriously hurt !

This has really got me thinking.....

I do have the 6 lug rear axel in my 86 Winnie , but it still has the 5 lugs on the front. It sounds like mine was upgraded , no ?

Now I am worried about the front 5 lugs. I understand these were not subject to recall , but that Toyota did make a 5 lug to 6 lug adapter for the front.

I had my Winnie weighed at a local landfill last year when I bought it , and with full water and propane (empty holding tanks and NO passengers) it weighed in at a WHOPPING 6800 lbs. !!!

Does this sound like my rig is SERIOUSLY overloaded ??

I am going to try and search for the 5 lug to 6 lug adapter , but I hear they are quite hard to come by.

Anyone know where I may find one ?

[motoyhomme]

Glad to hear no one was seriously hurt !

This has really got me thinking.....

I do have the 6 lug rear axel in my 86 Winnie , but it still has the 5 lugs on the front. It sounds like mine was upgraded , no ?

Now I am worried about the front 5 lugs. I understand these were not subject to recall , but that Toyota did make a 5 lug to 6 lug adapter for the front.

I had my Winnie weighed at a local landfill last year when I bought it , and with full water and propane (empty holding tanks and NO passengers) it weighed in at a WHOPPING 6800 lbs. !!!

Does this sound like my rig is SERIOUSLY overloaded ??

I am going to try and search for the 5 lug to 6 lug adapter , but I hear they are quite hard to come by.

Anyone know where I may find one ?

Yes, you probably have one of the converted units. These adapters did not add any beef to the front end, they were for installing the same wheel on front as on back. In addition to the adapters you would have to find two 6 lug rims for the front and one for the spare tire. These adapters are no longer manufactured by Toyota and very hard to find. There were never any recalls for the front and I never heard of any of the front wheels coming off.

I keep a spare tire for the 5 lug front and there are 4 tires on back. I once traveled 550 miles with one of the inside duallies flat and the other Yokohoma held on with no effect on either tire.

Allen

[Diesel_Aggie]

Here's a picture of the duals and outer axle. The picture of the rear of the Sunrader on the ground didn't come out well....I was trying not to get run over and was in a hurry to get to the airport. I'm the pilot so missing the flight was not an option! I'll get some more pics when I can. I did get some fiberglass damage in the rear of the left wheelwell where the duals hit. It's about an 8" crack wrapping from inside the wheelwell to the outside. Won't be too hard for the fiberglass shop to fix. The left rear fender flare is totally gone. Any ideas other than RV salvage yards where I could find one? I think something could be fabricated in it's place pretty easily. I find the factory ones quite ugly anyway.

Thanks to the poster (Diesel Mike I think) who gave the info on the '87-88 rear ends having the same width springs. If I can just drop the old axle/springs and bolt in the new one to the same mounts I'm in good shape. If the shock mounts are the same I'll be thrilled. I can handle making brake lines and parking brake cables. Metal fabrication/welding is not in my skill set. The picture will be very useful. Hope to compare this evening.

It's interesting someone on this board got the failure report within an hour of it happening! A bicyclist also pulled up behind me and was taking picture. I was on the phone with AAA and the towing company so didn't get the chance to talk with him before he disappeared. AAA offers a coverage level with +RV that you may want to consider. I get up to 100 miles of free towing that includes RV use. Used it here and last year when I broke an axle on the F-350 DRW with 33' 5th wheel hooked up.

[ChairmanMeow7]

So even if I could find the 5 lug to 6 lug adapters for the front , they really don't help safety wise , correct ?

I was going to ask how they could possibly help , as you still only have 5 lugs holding the adapter on (instead of the wheel).

I am still wondering if my rig sounds like it is SERIOUSLY overloaded.

I posted this question in about 3 differant threads , but have not recieved any answers yet.

My 86 Winnie weighs in at 6800 lbs !!!!!!

And that's will full propane and water , empty holding tanks , no generator and NO passengers !!

[turtle]

So even if I could find the 5 lug to 6 lug adapters for the front , they really don't help safety wise , correct ?

I was going to ask how they could possibly help , as you still only have 5 lugs holding the adapter on (instead of the wheel).

I am still wondering if my rig sounds like it is SERIOUSLY overloaded.

My 86 Winnie weighs in at 6800 lbs !!!!!!

And that's will full propane and water , empty holding tanks , no generator and NO passengers !!

What is the listed GVW on your coach? There should be a tag on it listing this figure.

The front hub adapters only make it so that all 7 rims have the same bolt pattern. Nothing more. From a safety stand point you have a single spare that can be used at every location.

If you want to beef the front suspension add 23mm torsion bars, a steering stabilizer, and Bilstein shocks. You can rip the front suspension off and replace the bushings with poly but you don't have a lot of weight on the front like you do on the back. I have never seen front bushings worn to the point of needing replacement but I am sure that this can happen given enough age and miles.

Being over weight can cause a number of issues such as suspension wear, shock failure, busing wear, inadequate braking performance, instability in handling to name a few.

I doubt that anything will "snap" but things will wear out faster

[ChairmanMeow7]

Where do I find the tag listing the GVW on my coach ?

I don't recall seeing anything inside the doors.

[mission mike]

Glad to hear no one was seriously hurt !

Chairman Meow Hi we had our 89 Winnie weighed at our local landfill too, the weight came in at 5060lbs, a lot less than yours! ours is the 22re with auto, no ac on the coach roof, half a tank of gas and most everthing else empty,

Mike

This has really got me thinking.....

I do have the 6 lug rear axel in my 86 Winnie , but it still has the 5 lugs on the front. It sounds like mine was upgraded , no ?

Now I am worried about the front 5 lugs. I understand these were not subject to recall , but that Toyota did make a 5 lug to 6 lug adapter for the front.

I had my Winnie weighed at a local landfill last year when I bought it , and with full water and propane (empty holding tanks and NO passengers) it weighed in at a WHOPPING 6800 lbs. !!!

Does this sound like my rig is SERIOUSLY overloaded ??

I am going to try and search for the 5 lug to 6 lug adapter , but I hear they are quite hard to come by.

Anyone know where I may find one ?

[shandamac]

The owner was mistaken, misrepresenting, or misinformed by the shop that did the repair on yours.

Your axle is still a 1/2 ton and prone to wheel loss.

Toyota did make some 1 ton 5 lug axles but they do not look like yours. They have full inner and outer bearings just like the 6 lug axles.

Your axle is a single bearing 1/2 ton axle.

DM,

Per your sage advice, I am on the lookout for a 1 ton axle to fit Sadie. I have some connections in auto salvage, and will be putting them on the prowl too. Glad to hear the 6 lug will fit the new tires the previous owner put on her. I'm cheap, but safety is first and foremost.

With all the detailed info this forum provides, I'm feeling more confident that we'll be able to fix Sadie up proper like, and enjoy her a long, long time.

shanda

[turtle]

Where do I find the tag listing the GVW on my coach ?

I don't recall seeing anything inside the doors.

I don't own a winnie but on my RBI it is on the coach body outside of the driver's door.

http://www.toymike.com/diesel/pics/dieselID.jpg

[Geysergazers]

This is just a point of information, as it makes no real difference RE 5Bolt dual overloading.

The Truck under our '82 Dolphin is what Toyota (according to the Owner's Manual) calls 3/4Ton, not 1/2Ton. The 3/4Ton rear axle is rated to carry 2905Lb whereas the 1/2Ton axle is rated to carry 2540Lb. Again according to the Owner's Manual, the Cab&Chassis requires 1.9Qt of rear-end oil, whereas the 1/2Ton truck requires 1.8Qt in it's differential. A good Parts Man will ferret out the fact that Toyota assigns different part numbers to the 3/4Ton Axle Shaft and the 1/2Ton part. BTW, the Wheel Bearing is the same part for both axles.

Lew

[Yostfmx]

So when I weight my motorhome (with 5 lug) it has to be $3000 lbs. really if I want to keep 5 lug on, with the outside wheels off. I think I can do it maybe do it?...

[Rich Carl]

> Per your sage advice, I am on the lookout for a 1 ton axle to fit Sadie.

Shanda,

I have for sale a one ton, full floating, 6 lug nut axle with 4 dually rims that came off a 1990 Toyota motorhome with 21k miles that unfortunately was totalled out. The rear end was undamaged. I may be able to deliver it for a modest fee. I am located in Michigan. Email me if interested at:

Rich_Carl@yahoo.com

Rich

[WME]

So when I weight my motorhome (with 5 lug) it has to be $3000 lbs. really if I want to keep 5 lug on, with the outside wheels off. I think I can do it maybe do it?...

You got it. The axle will still be a weak link. BUT with a single tire the load will be centered and things will work like Toyota designed them to.

195/14/lt has a capacity of 2100lb, a 195/70/15lt has a capacity of 200lb and has the same rolling dia, so your speedo will still be on. But you will need a new set of rims

[Stevo]

And did those 5 lug 1 ton axles have the protruding hub surrounded by the little bolts like a normal 6 lug 1 ton axle?

Toyota did make some 1 ton 5 lug axles. They are VERY uncommon but they do exist.

[Derek up North]

No. AFAIK, they are not 'Full Floating'.

[Stevo]

I have a few questions about changing the gearing with your 1 ton axle please...

1) You said the 4:56:1 gearing had improved performance over the 4:10:1 gearing... Specifically what is the difference between the two? Better MPG??

2) Do you think I would get the same "improved performance" you got if mine if this gear change was done on an 18' Sunrader with a 5 speed transmission?

3) How much more time and money did it take to change the gearing?

Thank you.

Make sure you get an axle with 4.10:1 gearing. You do not want 3.90:1 gearing. I replaced the ring and pinion in my donor axle with 4:56:1 gearing and am VERY happy with the improved performance.

[Stevo]

What does "AFAIK" mean?

No. AFAIK, they are not 'Full Floating'.

[Derek up North]

As Far As I Know.

[zero]

If anyone has put the '87 up DRW axle in a 1979-1983 Toyota RV please contact me. I'm still not sure how the later model rear end attaches to the older body style. Is fabrication required? I know Toyota supplied the conversion kits to the RV manufacturers that included the proper brackets for each body style. I am unable to find valid part numbers for this kit or bracketry. I assume I need to get the springs along with the axle and wheels? Thanks.

On edit I'd like to add that mileage is 99,000 and I've never had more than 200 pounds inside since I've owned it.

I just put a dually FF from a 1987 Toyota into a 1978. I can pretty much tell you all you need to know for the swap along with part #s. In brief - unless the dually axle comes out of an older motorhome - you'll need to cut the spring perch mounts off it and reweld. The older truck frames and springs are two inches narrower. If you want the front to match, all the parts should be a bolt-in swap as long as you have a torsion-bar front end. If you have coil springs - the front 6 lug hubs will fit but you need to reuse the original brakes.

Had you inspected your rear axle before it failed to confirm the bearings were good and the axles were not loose inside the differential carrier? I ask because from what I've heard and read - the axles rarely fail without warning unless they have the "fake" duals on them. What exactly failed in yours? Did an axle actually snap or did it just come out due to a failed retainer inside the carrier?

[zero]

So when I weight my motorhome (with 5 lug) it has to be $3000 lbs. really if I want to keep 5 lug on, with the outside wheels off. I think I can do it maybe do it?...

Toyota motorhomes tend to have a lot of overhang well beyond the rear axle. When you climb a hill much of the vehicles total weigth transfers to that rear axle. Weight is a lot more even when on flat land. It's very easy to overload the rear. As I recall the Toyota "1/2 ton" rear axle itself is designed to carry a max of 3600 lbs. and live a "normal" life. Axle weight ratings when posted on ID tags take into account other factors including wheels, tires, springs, brakes, etc.

[zero]

I assume I need to get the springs along with the axle and wheels? Thanks.

No you don't have to change the springs. You probably WILL have to change the bottom brackets that hold the U-bolts and shock bottoms. You will also need new u-bolts since the FF axle is likely to be a larger OD. And if you want to add any leafs to your spring packs you'll need some new 3/8" centerbolts ($5 each). Depending on what you swap in the brake hydraulics - you might want to add a manual adjustable brake proportion valve. Only costs $20 and you mount it under the hood by the master cylinder. It will correct any brake mismatch from the larger brakes in the new rear axle. Using a manual valve makes more sense to me than using the Toyota weight-sensing valve in back. That weight sensing valve was installed for vehicles that get drastic changes in weight - .e.g. an empty or fully loaded truck. RVs are always heavy and pretty consistent.

[MontanaChinook]

Glad you're ok!

You got it. The axle will still be a weak link. BUT with a single tire the load will be centered and things will work like Toyota designed them to.

195/14/lt has a capacity of 2100lb, a 195/70/15lt has a capacity of 200lb and has the same rolling dia, so your speedo will still be on. But you will need a new set of rims

This is what I'm hoping will save me...I have a 78 Chinook. It's the bigger, "Newport" model. Single rear wheels. It might have a bit of a low rating, but its passable, right? The big problem was the "fake" duallys, right?

If there were heavy duty axle shafts and heavy duty bearings I could buy that were a direct swap, I'd definitely like to do that.