zero Posted December 2, 2012 Share Posted December 2, 2012 I posted earlier about my attempts to retrofit 1987 1 ton hubs and FF rear axle into my 1978 Chinook. I don't want to have a rig that needs two spare tires. A 1978 Toyota has a totally different front end then later trucks. Coil springs and steering linkage behind the front axles. Later trucks have torsion bar and steering linkage in FRONT of the front axles. I've been driving myself nuts trying to get the big-bolt pattern 6 lug hubs on the truck. The wheel bearings for all the trucks are the same so the hubs themselves interchange. The problem is brakes. Well - after a lot of messing around . . . I've decided it's virtually impossible to get the big brakes on. They cannot go behind the front axle (like in later trucks) because the steering linkage is there and in the way. So, I made an adapter and mounted the brakes in front. Great, right? Well, maybe not. When the brake calipers are in front - and I make a sharp turn - they hit the stabiilzer bar end. No good. Now - after wasting many hours on this failed attempt - I'm on to a new idea. Since only the older smaller brake calipers will fit - but they will not work on the 1 ton rotors - I am adapting the original 1/2 ton rotors to bolt on to the 1987 hub. They are originally 5 hole and bolt to the original hub with five bolts into a threaded hub., The 1987 1 ton uses an odd-ball 6 hole rotor and the threads are in the rotor - not the hub. So, I drilled out the 5 lug rotor for a 6 hole mount. I was just barely doable. No threads now on either side so it will fasten with six grade eight 7/16" bolts and nut s. . or some 10 m by grade 10.9 if I can find some locally. Looks like this will work fine. The only machining needed is to either take off 1/32" from the OD of the hub casting - or enlarge the center-hole of the rotors by 1/32". Here is the original 1/2 ton steering knuckle with the 1 ton brake caliper mounted in front with an adapter I made. I hits the stabilizer link when turned far right. No good. Here's what the 1/2 ton knuckle looks like with the orignal 1/2 caliper in its original mount (on left) and the 1 ton added on the right with an adapter I made Here is the 1/2 ton, 1/2" thick solid rotor sitting on top of the 1987 1 ton hub that takes the dually-type wheel. Rotor much be lowered to where the step is on the bottom. Here is the original 1/2 ton five-bolt rotor with new holes drilled to make it a 6 hlole rotor. Not easy to do but worked out fine. Quote Link to comment Share on other sites More sharing options...
WME Posted December 2, 2012 Share Posted December 2, 2012 Lame Brain question !!! Can you make an insert for the 1/2 ton caliper so spread it apart far enough so that it will fit on the 1 ton rotor?? No increase in pad area but you would get a vented rotor to help with fade. Quote Link to comment Share on other sites More sharing options...
zero Posted December 2, 2012 Author Share Posted December 2, 2012 Lame Brain question !!! Can you make an insert for the 1/2 ton caliper so spread it apart far enough so that it will fit on the 1 ton rotor?? No increase in pad area but you would get a vented rotor to help with fade. Good question. That was one of the ideas I was originally pondering. I'd have to make some sort of separator plate and it would need to be a 1/2" thick. I'd have to be able to seal it. I haven't had one of those dual piston calipers split apart - but i suspect only one side has a counterbore to hold an o-ring. That would mean that the new 1/2" thick adapter "spreader" plate would need to be cut on one side to hold a 2nd o-ring. It would be extra work for not a lot of gain. Braking power wouldn't be enhanced but I would have an air-cooled rotor instead of solid. I was kind of hoping to find a Sumitomo fixed caliper a lttle bigger and for a wider rotor - but I don't know if a bolt-on caliper like that exists. If I owned a huge junkyard full of foreign trucks - I'd be yanking a bunch to measure. Quote Link to comment Share on other sites More sharing options...
zero Posted December 7, 2012 Author Share Posted December 7, 2012 Lame Brain question !!! Can you make an insert for the 1/2 ton caliper so spread it apart far enough so that it will fit on the 1 ton rotor?? No increase in pad area but you would get a vented rotor to help with fade. Just found out that widening the caliper would not work. I also found out that even the original caliper with the 1 ton hub added would rub on the hub. I had to grind a slight amount of the hub OD to make it all work. Finally got it though. Redrilled the original five-lug rotors for 6 holes. I bought some headed metric bolts and nuts in Grade 10.9 (equiv to US Grade 8) and spaced out with hardened spacers by 3/8" of an inch. It all fits perfect now. Here's the completed 1978 front knuckle and the 1/2 ton rotor bolted to the 1 ton 6 lug hub. Grade 10.9 headed bolts with one flat ground on each so it locks in place. Grade 10.9 nuts on the outside - with Loctite and torqued to 65 lbs. Quote Link to comment Share on other sites More sharing options...
Totem Posted December 7, 2012 Share Posted December 7, 2012 Wow... impressive. how did you line everything up so perfectly? is it catawampus? would it effect balance? Quote Link to comment Share on other sites More sharing options...
zero Posted December 7, 2012 Author Share Posted December 7, 2012 Wow... impressive. how did you line everything up so perfectly? is it catawampus? would it effect balance? The original center-hole in the 1/2 ton rotors fits the 1 ton hub near perfectly so it is automatically aligned. The 6 bolts just hold it in place, they don't determine how centered it is. Quote Link to comment Share on other sites More sharing options...
zero Posted December 7, 2012 Author Share Posted December 7, 2012 would it effect balance? The holes I drilled and bolts I added are too far inboard to effect the balance (I assume). Quote Link to comment Share on other sites More sharing options...
Totem Posted December 7, 2012 Share Posted December 7, 2012 wow with that much effort put into this I would sent those rotors to be cryo hardened. otherwise you may need to do this again. Quote Link to comment Share on other sites More sharing options...
zero Posted December 7, 2012 Author Share Posted December 7, 2012 wow with that much effort put into this I would sent those rotors to be cryo hardened. otherwise you may need to do this again. The effort to actually do the work is very little. Most of my effort was wasting time with trial and error and many failed attempts at this. Now that I know what works, it is easy. Makes me have a lot of respect for factory built trucks. When all it right it looks pretty simple. We don't get to see all the man hours spent on engineering. We just see the finished product. Quote Link to comment Share on other sites More sharing options...
Up north mi Posted February 23, 2016 Share Posted February 23, 2016 Hi DJ have you put them on and tried them? I have a 1978 Mh that I would like to do any tips? Thanks brian Quote Link to comment Share on other sites More sharing options...
zero Posted February 23, 2016 Author Share Posted February 23, 2016 Yes, I have the 6 lug, one-ton hubs on the front my 1978. It's a lot of work and unlike when done on newer trucks, you have to keep the original brakes and rotors. But if you are swapping in a full-floater in the rear - it is nice to have the front match the back and only have to carry one spare tire. Quote Link to comment Share on other sites More sharing options...
fred heath Posted February 23, 2016 Share Posted February 23, 2016 (edited) JD, I have the 8 lug GM rear. I'm in the process of having 8 lug adapter plates frabricated out of 1/2" steel plate. This will involve punching out the original 5 lug studs on the hub and replacing them with grade 8 nuts and bolts to attach the new adapter plates to the hub. This will add an extra 1" to the front axle width, but do away with having to carry two spares. Nice thing is I get to keep all the original brakes and calipers. Not sure if this will work with Toyota 6 lug rims. Edited February 23, 2016 by fred heath Quote Link to comment Share on other sites More sharing options...
zero Posted February 23, 2016 Author Share Posted February 23, 2016 Fred - seems that should out very well. I assume you don't have that huge wheel-offset to deal with since you don't have duallies. Quote Link to comment Share on other sites More sharing options...
zero Posted February 23, 2016 Author Share Posted February 23, 2016 Poor Chinook REALLY needs a paint job. I've put new doors on it since the photos, along with a new windshield and a lot of interior work. Also has a built-in propane tank now, along with the 2nd gasoline tank. In the photo of my three micro-minis - only the Datsun lacks front wheels that match the back. Has a factory full-floater in the rear with a real odd-ball 6 lug pattern (odder then what Toyotas use). I am hoping to paint the Chinook this Spring IF I get the new shop finished and have some heat. Quote Link to comment Share on other sites More sharing options...
Up north mi Posted February 23, 2016 Share Posted February 23, 2016 Nice rigs I found a full floater on craigslist that has never been used I had to put new bearings in the third member. I installed it last summer with new springs thanks to the forum. Now I am going to do the front. Found used hubs from somebody from Mt pleasant mi. Got them yesterday. Have to get rims yet they are costly. thanks again everybody on the forum I could not have done it without it .l have bunch of other projects to do Quote Link to comment Share on other sites More sharing options...
zero Posted February 23, 2016 Author Share Posted February 23, 2016 I think I have some extra rims I might sell. I have to count. I already sold a few to people on this forum. it is an old USA wheel-pattern that IH, Dodge, Ford, and Studebaker used on mid-sized trucks. But those are in 16" and 17" tire sizes - not 14" like Toyota uses. New Korean military vehicles still use the same pattern. Quote Link to comment Share on other sites More sharing options...
zero Posted February 23, 2016 Author Share Posted February 23, 2016 I just looked down my basement and I have three extra Toyota rims. Also two extra Nissan-Datsuns (for full floaters). I might sell two of the Toyota wheels if you can't find somewhere else. These are rusty but sound. Need to be cleaned up and painted. Contact me by private message if you can't find anywhere else. I'm in northern Michigan. If you call this junkyard in northern NY and get lucky enough to get old man Juliano on the phone . . ask him about the 1983 Sunrader sitting in his woods. I was there a while back and stripped some parts off of it. Has the full-floater conversion and also the 6 lug hubs in front. Had 6 wheels and tires when I looked at it. Rear axle has a rust-hole right through it. If the old man is still alive - and has not scrapped it yet - he'd sell the wheels. Note - you have to talk to him only. If anyone else gets on the phone - they'll tell you there are NO Toyota RVs in their yard. Place is Juliano's and you need to speak to old man Juliano himself. He's near 90 years old so can't even say, for sure, if he is still alive today. Address: 4735 NY-14, Sodus, NY 14551 Phone:(315) 483-4607 Quote Link to comment Share on other sites More sharing options...
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