Swap out 1/2 ton wheel hub for 1-Ton

[zero]

I finally got the two Sunraders (84 w/ 1 ton axle and 82 w/ 1/2 ton axle) together yesterday and its clear that the points where the top of the shock absorbers attach to the frame of the Sunraders are in different places. So to do the swap I will need to have brackets welded on to the frame on both vehicles.

A few questions please...

1) Does anyone know what you call the brackets that the top part of the shocks attach to and where I can buy them?

2) Would that bracket be the same for both vehicles? In other words, is the bolt or hole size for the top attachment of the shock absorber the same for all shock absorbers?

3) I haven't measured to see if the point where the leaf springs attach to the vehicles frame is the same length between both of them. Does anyone know if that could be a different length too? (Aaargh, I hope not because that could really complicate this axle swap!)

Thanks.

Why do you feel it's necessary to change the top shock mounts? An alternative is just change the bottom mounts and keep the frame mounts as they are.

I assume the 82 has both the top shock mounts welded to the crossbar in front of the axle. The 84 probably has staggered shock mounts - one in front of the axle and one behind and both welded to the top of the frame (not the crossbar). If that is the case and you want to swap . . . just swap the bottom u-bolt plates. No big deal as I see it. Much easier then trying to change the frame mounts.

The 82 shocks are 1 " shorter then the 84 1 ton shocks if they are mounted as I described. The 1/2 ton shocks are 20.7" extended-12.5" closed, whereas the 1 ton shocks are 22.7" open and 8.9" closed.

1986 and newer rear axles on Toyota trucks are 3" wider then older trucks. Same with the frames and same with the spacing of the leaf-springs. If your dually FF was already installed in a 84 Sunrader then the spring perches were already cut off and rewelded to the same location as your 82.

I think you're making it more complicated then you need to. To put the dually FF into the 82 - you cannot use the original 82 bottom brackets because the 82 axle OD is smaller diameter at 2.5". You need bottom brackets to fit the curve of a 3.15" axle OD diameter (that's what the FF has). Chevy 1/2 trucks, Blazers, Suburbans, etc from 80s-90s use the same diameter in 1/2 tons. Easy to find. Take two of those brackets and weld your old 1982 bottom shock mounts to them and they will work fine.

When you go to put the 1982 1/2 ton axle into the 1984 - you will have problems since you need the bottom brackets with the small axle fit (2.5") and with staggered shock mounts (one pointing forward and one pointing back). I would reuse the brackets from the 1982 and relocated the shock mounts on them via an arc welder.

Modifying the bottom brackets (that unbolt) will be much easier then trying to modify the top shock mounts if what you have now is as I described.

[Derek up North]

I'd suggest leaving the shocks uninstalled when you first put it together. Then measure the spacing between shock mounts. Only then decide which shocks to use to keep them in their proper working range.

[Stevo]

Your input really helps a lot and is a huge relief because I was stressing out after seeing how the top mounts were different, so thank you!

There is a lot of surface rust under the 82. It seems like the kind of rust that mostly could be wire brushed off. Is that rust something to be concerned about? And if so, what do you think about me wire brushing the rust when we have it jacked up and supported and then using something like this Kleenstrip stuff http://tinyurl.com/awt7n24 or Chassis Saver http://tinyurl.com/b8do9td or POR-15 http://tinyurl.com/beqk9n4 ?

[Derek up North]

I haven't heard much talk about any other than POR-15. Wear gloves and old clothes. It sticks to skin very well!

[zero]

Your input really helps a lot and is a huge relief because I was stressing out after seeing how the top mounts were different, so thank you!

There is a lot of surface rust under the 82. It seems like the kind of rust that mostly could be wire brushed off. Is that rust something to be concerned about? And if so, what do you think about me wire brushing the rust when we have it jacked up and supported and then using something like this Kleenstrip stuff http://tinyurl.com/awt7n24 or Chassis Saver http://tinyurl.com/b8do9td or POR-15 http://tinyurl.com/beqk9n4 ?

To a degree, rust impedes the formation of new rust. Once you wire-brush it, it will rust faster unless you seal it from moisture; i've used POR-15 and Zero-Rust. My preference is Zero-Rust when it's priced reasonable but either are good products. I've also used good-old-fashioned Rustoleum "Rusty Metal Primer" and it works reasonably well as long as you top coat it with paint. It takes two full days to dry though so priming and painting can be a long process. Zero-Rust dries rock-hard in a few hours. I live in a area where roads get salted summer and winter. Rust gets pretty bad. A wire brush on some of the bad stuff is useless and I have to use a welder's slag hammer (like a pick hammer) to get the rust off. i just redid the entire frame on my 1978 Toyota. It was from Louisina and only had light surface rust. It was a pleasure to work on compared to NY stuff.

http://www.zerorustusa.com/

[90toydolphin]

another option for the rust is phosphoric acid, rust mort one product, there are others. cheap. the only thing is you have to paint after it dries.

[5Toyota]

i owned a 1987 4wd 22r carb with a G52 and it was geared much different then THE W 56 i am not sure when they replaced the w 50 WITH THE W56. the w 50 is the older version used in the 1970s

[Stevo]

I finally got both vehicles together so the mechanic was able to check them out side by side and this is what he texted to me...

"I'm thinking I might run into some problems taking off the lower u bolts. If they break we will have to spend the money to get new ones."

Are u bolts expensive and is there a specific kind of u bolt I will need to get?

[zero]

I finally got both vehicles together so the mechanic was able to check them out side by side and this is what he texted to me...

"I'm thinking I might run into some problems taking off the lower u bolts. If they break we will have to spend the money to get new ones."

Are u bolts expensive and is there a specific kind of u bolt I will need to get?

Some auto-parts stores and any good spring shop has a u-bolt machine that makes them from straight threaded rod-stock. I just had two made and they were $9 each with a pair of nuts and hardened washers. The original Toyota u-bolts are 1/2" diameter. U-bolts for a 1/2 ton Chevy or GMC 1/2 ton truck, Suburban, van, etc. also fit the Toyota FF axle. They are slightly more HD at 9/16": diameter.

[Sunrading Arkansas]

@Stevo

I posted pics on how I resolved my upper shock mount dilemma here: http://toyotamotorhome.org/forums/index.php?showtopic=5382

It also shows jdemaris's solution as well. I'm no suspension expert so take mine with a grain of salt.

As for rust, for my surface rust I've been slowly brushing/wire-wheeling mine and treating it with Rustoleum Rust Reformer. You can buy it in bulk or aerosol cans. I've been using the aerosol because 1) I'm lazy 2) you can spray it into nooks and crannies that you otherwise couldn't reach.

Just my 2 cents.

-Patrick

Edited January 30, 2013 by Sunrading Arkansas

[Stevo]

Hey thanks for letting me know about your thread. :-)

@Stevo

I posted pics on how I resolved my upper shock mount dilemma here: http://toyotamotorhome.org/forums/index.php?showtopic=5382

It also shows jdemaris's solution as well. I'm no suspension expert so take mine with a grain of salt.

As for rust, for my surface rust I've been slowly brushing/wire-wheeling mine and treating it with Rustoleum Rust Reformer. You can buy it in bulk or aerosol cans. I've been using the aerosol because 1) I'm lazy 2) you can spray it into nooks and crannies that you otherwise couldn't reach.

Just my 2 cents.

-Patrick

[Stevo]

Did you have yours made with 9/16" material? Why did you have a spring shop make new ones instead of buying off-the-shelf u-bolts for a 1/2 ton Chevy or GMC?

Thanks

Some auto-parts stores and any good spring shop has a u-bolt machine that makes them from straight threaded rod-stock. I just had two made and they were $9 each with a pair of nuts and hardened washers. The original Toyota u-bolts are 1/2" diameter. U-bolts for a 1/2 ton Chevy or GMC 1/2 ton truck, Suburban, van, etc. also fit the Toyota FF axle. They are slightly more HD at 9/16": diameter.

[Stevo]

Did you use this Rust Reformer http://tinyurl.com/bjrcmtj or this Rust Reformer http://tinyurl.com/bz9j2uz ? The first one (at Home Depot) seems to be an all-in-one rust remover and paint and the stuff at Walmart is a rust remover only.

[zero]

Did you have yours made with 9/16" material? Why did you have a spring shop make new ones instead of buying off-the-shelf u-bolts for a 1/2 ton Chevy or GMC?

Thanks

I didn't go to a spring shop (nearest is 60 miles from here). The local Car Quest autoparts store here has a U-bolt bender. I had them made because - if I used the Chevy u-bolts on my Toyota - I'd have need more U-bolts later for the Chevy I'm working on. I got 9/16" bolts - but the original 1/2" like Toyota had I'm sure would of been fine. If you get looking at over-the-counter u-bolts, the smallest is usually 9/16" and the go up to 5/8", 3/4", etc. 1/2" in truck standards is tiny (Toyota probably calls them 13 mm).

The FF rear has a tube OD of 3 1/8" but - it has a raise welded seem that calls for extra clearance. You need round u-bolts with 3 1/4" space between them and if 1/2" diameter - 3 3/4" on center.

Here's the pair you need for $17

http://www.autoandtrucksprings.com/products/1_2x3_1_4x8_3_4_ROUND_U_BOLT_KIT-1798-89.html

[Sunrading Arkansas]

@Stevo - I used the Home Depot one (same label) but bought it at Wal-Mart. It is an all-in-one, goes on black, but is paintable.

[Stevo]

Thanks!

The FF rear has a tube OD of 3 1/8" but - it has a raise welded seem that calls for extra clearance. You need round u-bolts with 3 1/4" space between them and if 1/2" diameter - 3 3/4" on center.

Here's the pair you need for $17

http://www.autoandtrucksprings.com/products/1_2x3_1_4x8_3_4_ROUND_U_BOLT_KIT-1798-89.html

Are you going to bother painting after? What do you guys think about using the Rustoleum Rust Reformer and then spraying that undercoating in a can stuff after that is like tar?

@Stevo - I used the Home Depot one (same label) but bought it at Wal-Mart. It is an all-in-one, goes on black, but is paintable.

[Sunrading Arkansas]

@Stevo I'm not painting over it. It is self sealing and goes on pretty thick, but I don't have to worry about salt on the roads down here. If I lived up north I'd be doing everything I could to keep that crap off the metal.

[Stevo]

I learned living in Hawaii to never ignore scratches through paint or little rust spots because I know they turn into gaping holes later, but I'm not sure if I should be concerned about surface rust on the frame of this motorhome that scales off with my fingers?? Anyone know? I plan on traveling a lot through the rainy tropics near the ocean so would it be wise for me to wire brush the chassis and paint it with Rustoleum Rust Converter?

[Sunrading Arkansas]

@ Stevo - That's what I'm doing, even though i don't live any where near the rust belt or the ocean and it is just minor surface rust. I think it's a good idea, if for nothing more than resale value and peace of mind. I think it'll probably take 10-12 cans of Rust Reformer to hit everything. I'm NOT going to wire wheel/brush everything, only the worst parts - the rest I am power washing and then treating.

[texascoastalrider100]

Hello everybody i have been reading up on this site from time to time and finally joined today and i need some help. I have decided to do the the swap on my 83 dolphin's front axle from 5 lug to six lug. I have found and purchased a true 6 lug front complete spindles including brake calipers and rotors from a 87 toyota motor home. Here is where i am at. The Spindle will not bolt up because the bottom a frame is differant. First option does anybody know if bottom a frames will interchange and solve the problem. Second I removed the hub and rotor assembly on both spindles and the six lug bolted right up to the old 5 lug spindle however the original 5 lug brake caliper does not line up with the 87 brake rotor not even close the 87 is tucked in closer to the spindle (note the brake rotor seems to be the same diameter however it is one quarter inch wider). The 6 lug 87 caliper is a totally differant animal also and does not fit onto the 83 spindle. If this has already been answered I am sorry I didn't find it confirmed anywhere. I really dont want to spend 400 dollars on adapters just seems like too pricy. Surely somebody has done this on a 83, 84s and up seem to be differant also body change year. Any help will be appreciated thanks. There really doesn't look like a lot of differance in the strenght of the 6 lug caliper than the 5 lug about the same brake pad area and caliper piston size.

[zero]

Hello everybody i have been reading up on this site from time to time and finally joined today and i need some help. I have decided to do the the swap on my 83 dolphin's front axle from 5 lug to six lug. I have found and purchased a true 6 lug front complete spindles including brake calipers and rotors from a 87 toyota motor home. Here is where i am at. The Spindle will not bolt up because the bottom a frame is differant. First option does anybody know if bottom a frames will interchange and solve the problem. Second I removed the hub and rotor assembly on both spindles and the six lug bolted right up to the old 5 lug spindle however the original 5 lug brake caliper does not line up with the 87 brake rotor not even close the 87 is tucked in closer to the spindle (note the brake rotor seems to be the same diameter however it is one quarter inch wider). The 6 lug 87 caliper is a totally differant animal also and does not fit onto the 83 spindle. If this has already been answered I am sorry I didn't find it confirmed anywhere. I really dont want to spend 400 dollars on adapters just seems like too pricy. Surely somebody has done this on a 83, 84s and up seem to be differant also body change year. Any help will be appreciated thanks. There really doesn't look like a lot of differance in the strenght of the 6 lug caliper than the 5 lug about the same brake pad area and caliper piston size.

I put the 6 lug hubs on my 1978. The big change in the Toyota pickups is the change from front coil spring suspsension over to torsion bar suspension. I'm not sure which year the change took place. I have a 78 and 81 that are coil spring. My 87 is torsion bar. All the HD Toyotas with 6 lug 7.25" bolt-circle wheels were made for only trucks with torsion bar front suspension.

If you have a coil-spring truck with upper and lower control arms on both sides - there's only one way to install the OEM hubs and make it all work (that I know of). You install the 6 lug spindles in place of the original 5 lugs spindles. You reuse the original brakes and drill out the original brake rotors to accept 6 lugs. The rotors also have to be shimmed. When done you get tge 6 lug setup in front but not the newer and bigger brakes. I can post photos again if you want.

[zero]

Here are some photos. The work itself is not difficult. Figuring it out for the first time is. You just redrill the 5 hole rotor to accept 6 holes so the rotor can be bolted to the new 6 lug hub. it gets shimmed a bit with washers and you'll need to buy some new metric bolts (grade 8 or 9). The cast OD of the new HD hub then needs a slight amount of grinding for proper clearance.

[85Diesel]

1986 and newer rear axles on Toyota trucks are 3" wider then older trucks. Same with the frames and same with the spacing of the leaf-springs. If your dually FF was already installed in a 84 Sunrader then the spring perches were already cut off and rewelded to the same location as your 82.

Just wanted to point out that while the rear axles on 86 and newer trucks are wider, the frames are not. 84 and 85 has the same frame width as the later trucks, the axle can be swapped right over with no mods.

[zero]

Yes, but also note the early trucks e.g. 1978shave narrower frame rails then later trucks e.g. 1986.

[texascoastalrider100]

Thanks for the response jd.Why did you have to space out the spindle with washers what was rubbing. I went back and bought the upper and lower a frame's and I am planning on changing them out to try and make this work. Will let you know. My 83 truck has torsion bar suspension just like the 87. The lower a frame is the only thing that looks differant so far.

[zero]

Thanks for the response jd.Why did you have to space out the spindle with washers what was rubbing. I went back and bought the upper and lower a frame's and I am planning on changing them out to try and make this work. Will let you know. My 83 truck has torsion bar suspension just like the 87. The lower a frame is the only thing that looks differant so far.

I had to shim the rotors out so that were the proper distance from the brake calipers. The older trucks with coil-spring suspension have double-piston stationary calipers and there is little room for error. The later trucks have calipers with a floating single-piston setup. As to the rubbing? I don't remember exactly where the 1 ton hub was rubbing but it was a minor issue. I had to grind off less then 1/16th of an inch.

[Stevo]

Besides being able to use the same wheels that are on the back for front spare tires, are there any other advantages to having 1 ton front wheels?

[zero]

Besides being able to use the same wheels that are on the back for front spare tires, are there any other advantages to having 1 ton front wheels?

No. If you swap the front hubs on a later truck that has torsion-bar suspension, your gain includes bigger brakes. Not on the older coil spring trucks.