JakeNShannon Posted October 21, 2014 Share Posted October 21, 2014 Hello World! My wife and I are new owners of a cute blue & white 1978 Toyota Keystone Micro-Mini. We found it locally on Craigslist for $2,300, with much recent brake work and water pump job, etc. at 41,000 miles with all original 4spd, 20R, factory AC, etc. 1/2 ton 5-lug 'fooly' axle with tires from 1992 that look unused. We just got married and this was our wedding gift from my parents :-). We love it so far! It has a bed over cab, porta-potty in closet, small gas/elec fridge, 2-burner stove, sink with small fresh H2O tank (no grey/black tank in system though), propane furnace and rear dinette/twin bed. Everything works, and all appears to be in good shape overall (except some water damage on false wall above fridge and cab-over bed area). I have a handle on the required repairs in those areas, as well as the roof/vent/wall seams that need to be repaired, cleaned & sealed... My current major concern and questions are pertaining to the tires, driveline / axle. I believe my shocks need replacing, as the ride is very bouncy. I have 2 new Hankook RA08 195R14C LR Ds in the front and a 'modern' 185r14c LR D spare.. They are overkill and I think rub slightly in full turn on bumps in parking lot. I am considering moving them to the rear axle to replace the duallys and putting new Hankook 185R14s up front for slightly more clearance. The tires that came off the front were manufactured in 1992: passenger car tires 205/75r14 max 34psi, and the rears are same size/style. Tread is like-new but these are old, though surprisingly little dry rot, far older than I expected from visual inspection. There is no sticker in the door jamb, but the Keystone sticker on the camper says:GVWR 4,600#Front GAWR 1,850#Rear GAWR 2,900# We just took the RV on a 300 mile round trip excursion to the Virginia Northern Neck from Batesville, VA with no issues. Had it for about 2 weeks and 500 miles total running around getting parts, tires, etc. On the way back I found a CAT Scale and got our Toy weighed, here's where I'm at with me, my wife, 2 dogs at way back on dinette bed, full propane, half full on gas, no water, and some bedding/food/misc for the overnight trip--I would expect only a few hundred more lbs with everything I would ever want to bring with me: Front axle: 1,700# Rear axle: 2,780# Total weight 4,480# I have read a LOT about these axles and see varying oppinions on the axle safety, but am really not interested in an axle replacement unless absolutely necessary. This Toy being reasonably light and only a 16 footer makes me thing that I can get away with this with reasonable peace of mind from what I've read, but nothing seems conclusive. I never saw a response to a similar rig @ http://toyotamotorhome.org/forums/index.php?showtopic=6&p=22982 I do not like the dually fooleys in the back and am thinking I can get away with two single Hankook RA08 14" 195R14Cs in the back @ 65psi and run two 14" 185R14Cs up front @ 50psi reasonably safely with a rear bearing servicing / replacement? I am also interested in hearing about what issues I might experience with this setup affecting stability, traction, steering, ride quality, fuel economy, etc. The new tires are heavy, but going from dually to single should improve mpg! Thanks much in advance, and pics of the weight and us attached! Jake Quote Link to comment Share on other sites More sharing options...
WME Posted October 21, 2014 Share Posted October 21, 2014 Google and find the GVWR for just the Toyota P/U. See how close your are. Removing the foolies and replacing them with single is good for the axle and bearings, but the reduced axle width makes for a tippier ride. You choose. Quote Link to comment Share on other sites More sharing options...
Derek up North Posted October 21, 2014 Share Posted October 21, 2014 1978 Dolphin's were listed with a GVWR of 4600lb, so I suspect this is also the way Toyota would have rated them. It seems to me that you'd be OK running single rear wheel. Personally, I'd try to combat any potential sway from switching from duals by installing a sway bar. If there's one already there, then a bigger one. Quote Link to comment Share on other sites More sharing options...
JakeNShannon Posted October 21, 2014 Author Share Posted October 21, 2014 Google and find the GVWR for just the Toyota P/U. See how close your are. Removing the foolies and replacing them with single is good for the axle and bearings, but the reduced axle width makes for a tippier ride. You choose. Thanks, I have searched a good bit and can't really find anything in this department. I am under the stated coach ratings, and as I have read it seems coach manufacturers seemed to lower the weight ratings, not raise them. At this point I'm running the outer tires at a lower pressure and am thinking that the stiffer sidewalls of the 8-ply LR D tires would compensate for the reduced width, especially given that that tires are not likely adding that much stability in reality due to the lower pressure and lever effect on the axle shaft. Seems like it would be better to be a little tippier in general and drive more cautiously than to have the wheel snap off while confidently flying around a curve. I guess it is all subjective and up for interpretation. 1978 Dolphin's were listed with a GVWR of 4600lb, so I suspect this is also the way Toyota would have rated them. It seems to me that you'd be OK running single rear wheel. Personally, I'd try to combat any potential sway from switching from duals by installing a sway bar. If there's one already there, then a bigger one. Thanks for that info. I believe there is already a rear end sway bar, but it is fairly small. I think new single tires and beefing up the sway bar and new shocks would probalby make it feel better than it is now. Thanks for the insight! Quote Link to comment Share on other sites More sharing options...
Derek up North Posted October 21, 2014 Share Posted October 21, 2014 You could always try some bigger wheels! Quote Link to comment Share on other sites More sharing options...
zero Posted October 21, 2014 Share Posted October 21, 2014 Hello World! My wife and I are new owners of a cute blue & white 1978 Toyota Keystone Micro-Mini. I have read a LOT about these axles and see varying oppinions on the axle safety, but am really not interested in an axle replacement unless absolutely necessary. This Toy being reasonably light and only a 16 footer makes me thing that I can get away with this with reasonable peace of mind from what I've read, but nothing seems conclusive. I do not like the dually fooleys in the back and am thinking I can get away with two single Hankook RA08 14" 195R14Cs in the back @ 65psi and run two 14" 185R14Cs up front @ 50psi reasonably safely with a rear bearing servicing / replacement? Neat little rig. I saw it over at Fuelly.com I assume it was called an 18 footer when sold new. That's the smallest I've ever seen listed made by Keystone. Model M-180-RD. Putting it along side an 18' Sunrader it looks pretty much the same length. If it was mine, I wouldn't be worried about the duallies on that semi-floating rear as long as the wheel bearings are in good shape. I don't see why duals are needed though. Good insurance I guess if you get a blow-out in back. That's up to you. RVs like Winnebago Lesharos and Phasars are just as heavy in back and only use single 14" tires. The Winnebago 205/75-14C-D tires carry 1850 lbs. each just as the Toyota and VW bus 185R-14C-D tires do. Two of those tires on the back exceeds the weight limits of that rear axle. I assume you know this but if not, the rear wheel bearings get no lube from any outside source. Unlike the heavier FF rear that does -even though it's not designed to. So on an older rig - it's a good idea to check those rear bearings and replace if there is any question about them getting loose or drying out. Cheap insurance and one pair of bearings and lock-rings will probably last longer then you keep the RV. Why do you want 195s in back? Do you want the larger diameter for some reason? In regard to what is on the rear now - are the inside wheels standard Toyota off-set for a single-wheel set-up or are they special made for the OEM dually setup? Shocks of course, sound necessary. If you want to stiffen things up a big, Rock Auto has the spring-assist shocks for sale pretty cheap for your year. $61 for a pair. I have them on my 78 Chinook but they were $49 when I got them on sale. If your rig has a rear stabilizer bar - I'd like to see photos. I've never seen an older narrow frame Toyota truck with a factory installed bar before. I added one to my 78 Chinook. Quote Link to comment Share on other sites More sharing options...
snail powered Posted October 22, 2014 Share Posted October 22, 2014 Take a close look at all the rubber bushings in the suspension components to make sure they are in excellent shape. At this age the original ones would be dried out hardened and cracking. Quote Link to comment Share on other sites More sharing options...
JakeNShannon Posted October 22, 2014 Author Share Posted October 22, 2014 You could always try some bigger wheels! ... Hehe, I think I'll pass on those. Neat little rig. I saw it over at Fuelly.com I assume it was called an 18 footer when sold new. That's the smallest I've ever seen listed made by Keystone. Model M-180-RD. Putting it along side an 18' Sunrader it looks pretty much the same length. If it was mine, I wouldn't be worried about the duallies on that semi-floating rear as long as the wheel bearings are in good shape. I don't see why duals are needed though. Good insurance I guess if you get a blow-out in back. That's up to you. RVs like Winnebago Lesharos and Phasars are just as heavy in back and only use single 14" tires. The Winnebago 205/75-14C-D tires carry 1850 lbs. each just as the Toyota and VW bus 185R-14C-D tires do. Two of those tires on the back exceeds the weight limits of that rear axle. ... Thanks! That's the only thing I can think of. It measures at about 16ft (need to remeasure as I used shoe lengths which should be right on at sz 11, but not 100% accurate) but is a true motorhome from what I can tell i.e. M-180-RD. It seems Keystone made a 16 1/2 M-165RD chassis mount cab over, but I'm not sure if that is what I have or not, especially with the factory fake dually setup and the hole in the cab roof going into the camper. The tires I got up front I wanted to be able to handle full weight of rear if I needed to swap around after a flat (this was before getting on a scale or replacing my antique spare tire with an 8-ply, and I needed tires asap and went with the 195R14Cs to be sure--they are not very much bigger, only $10 more, but max load single at 65psi = 2094lbs). I'm planning to shift the 195s to the back as I already have them and replace fronts with the 185s and run lower pressure as the front is pretty light, but I'll still benefit from the reinforced sidewalls. With the dually 205/75R14 tires on the rear now (welded oem single rim), the speedo is at 65 when I'm actually doing about 60/61, so I figure a slightly larger rear tire will make that more accurate, drop rpms slightly, and going to a much lighter single tire configuration will improve economy and power. Getting 2014 tires vs current 1992 tires will improve traction and going from passenger 34psi tires to 8-ply reinforced sidewall 65PSI tires will stiffen things up substantially and should more than compensate from losing dually, especially considering the mostly useless lower psi outer tire. I am aware of the grease packed bearings on this semi-floating axle setup, and plan to replace bearings preventatively soon. Previous owner told me about axle situation and said bearings had been packed just before he bought it, about 1/yr 5k ago, but I have no idea the age of the bearings. I am also planning to replace differential and transmission gear oil, looking to the Amsoil "Manual Transmission & Transaxle Gear Lube 75W-90" for transmission and Amsoil "Severe Gear 75W-?" not sure if I should go with the 90, 110 or 140 weight for the rear end. Thanks for the tip on the rear shocks, I will definitely pick up a set of the spring assist Monroe's. I will also look tonight and see if I am remembering the stabilizer situation correctly or not. I believe there is one back there, but will double check and get some pics if I do. Take a close look at all the rubber bushings in the suspension components to make sure they are in excellent shape. At this age the original ones would be dried out hardened and cracking. I will definitely be doing a full suspension cleaning, inspection, and greasing, along with new shocks and bushings where needed etc. Quote Link to comment Share on other sites More sharing options...
zero Posted October 23, 2014 Share Posted October 23, 2014 Hehe, I think I'll pass on those. With the dually 205/75R14 tires on the rear now (welded oem single rim), the speedo is at 65 when I'm actually doing about 60/61, so I figure a slightly larger rear tire will make that more accurate, drop rpms slightly, and going to a much lighter single tire configuration will improve economy and power. I am aware of the grease packed bearings on this semi-floating axle setup, and plan to replace bearings preventatively soon. Previous owner told me about axle situation and said bearings had been packed just before he bought it, about 1/yr 5k ago, but I have no idea the age of the bearings. Something does not make sense (to me) in regard to the tire sizes. 205/75-14" is a tire with a bigger diameter that what comes OEM on most Toyota TVs. 185R-14C-D or 7.00 X 14". In that case, the 205/75-14" would make the speedometer read slow, not fast. A 195R-14C-D tires is same diameter as a 205/75-14" and should offer no change in speedo reading. 185R-14C-D is 25.6". 205/75R-14" is 26.1". 195R-14C-D is 26.2". This has me wondering if . . your's came OEM with bigger diameter tires (which I doubt), or someone changed the speedo drive gear in the trans, or someone changed the rear end gears? In reference to the rear wheel bearings- repacking them is not the usual way to service them. If they need grease, it also means they are likely worn. They usually just get replaced. They are sealed bearings and are installed very similar to what the older Ford F100s and F150s had in the rear. Single sealed ball bearing fastened to the axle with a pressed-on lock-ring. Quote Link to comment Share on other sites More sharing options...
JakeNShannon Posted October 23, 2014 Author Share Posted October 23, 2014 (edited) Something does not make sense (to me) in regard to the tire sizes. 205/75-14" is a tire with a bigger diameter that what comes OEM on most Toyota TVs. 185R-14C-D or 7.00 X 14". In that case, the 205/75-14" would make the speedometer read slow, not fast. A 195R-14C-D tires is same diameter as a 205/75-14" and should offer no change in speedo reading. 185R-14C-D is 25.6". 205/75R-14" is 26.1". 195R-14C-D is 26.2". This has me wondering if . . your's came OEM with bigger diameter tires (which I doubt), or someone changed the speedo drive gear in the trans, or someone changed the rear end gears? In reference to the rear wheel bearings- repacking them is not the usual way to service them. If they need grease, it also means they are likely worn. They usually just get replaced. They are sealed bearings and are installed very similar to what the older Ford F100s and F150s had in the rear. Single sealed ball bearing fastened to the axle with a pressed-on lock-ring. Interesting... I'm not too sure. I finally found the ID plate under the hood, it had been sprayed out of the factory with the rust prevention treatment and as covered in black goo. It says trans/axle L43 G082. It has the 4-speed and this indicates 4.11 gears. Funnily enough, when getting up to 70 on the speedo, the inaccuracy decreases and actual speed is closer to 67. Perhaps some mechanical wear of the speedo gear/cable confusing the issue. The primary reason I want the 195R14Cs in the rear is for the extra load capacity of the tires jumping up 250# to 2094# each vs 1850# of the 185R14Cs. Good further info on the bearings, thanks! I guess my only experience is with full floating axles with the taper/cone bearings. I understand what you mean now, and I'm probably due for new bearings for peace of mind shortly. I measured again and do in fact have 16' 8" from tail to front bumper, and about 78-80" wide excluding mirrors, as well as equipped with a rear sway bar, though I can't say if it is factory or aftermarket. I can say that it has been there a long time. Various pics attached of my rear suspension setup as it is, including the inner rim and brake backing showing the wheel offset... Edited October 23, 2014 by JakeNShannon Quote Link to comment Share on other sites More sharing options...
WME Posted October 23, 2014 Share Posted October 23, 2014 Looks like some one took a front sway bar and got a crafty and installed it on the rear axle Quote Link to comment Share on other sites More sharing options...
zero Posted October 24, 2014 Share Posted October 24, 2014 Yes, that DOES look a front sway bar. Nice job installing it back there. The OEM sway bar Toyota uses on the rear when installed in Toyota RVs has the main part of the bar attached to the rear-axle and the end-links attached to the frame. Your's is the opposite. Here's a 1987 sway bar installed in my 1978 Chinook. Also some axle photos comparing the 1978 semi-floater to a 1987 full-floater. That is ONE nice stack of leaf springs someone put together for your rig! Quote Link to comment Share on other sites More sharing options...
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