I have a 68 skylark that I put a 430 in, (engine specs are in street strip 400/430/455 section under "430 engine is stumbling") right now it has the stock non-posi 8.2 rear with a bop TH350 and the rear tires are 26.25 tall with 18'' rim Right now I have all brand new brakes, hardware, wheel studs, SS brake lines / drums, axle bearing & seals and fluid My questions would be: I was told a quote of $3,000.00 cash would get me a rebuild of what I have in the car now with a new limited slip posi and a set of 3.42 gears and he would also box in my control arms. (I know TA sells this same set-up) or they would sell & install a chevy 12 bolt rear with a new Detroit Eaton Trutrac with 31 spline axles, boxed in control arms and the gear of my choice. (will have to address driveshaft seperatly) or Keep it as is? Any help or other options would be really cool thanks, Tony
I would never spend $3000.00 on a rear, heres an option http://www.everyday-performance.com/positraction_axles.htm#!/~/product/category=578015&id=16389411
Have no fear, I'm not going to pay three grand for someone to change my gears. Take out the material cost and what do you have left? around $300 -400 bucks an hour labor charge. This maybe the going price rate, but not for me. Is the 8.5 the same overall length (drum to drum) as the 8.2? Will my new brake parts fit on the 8.5? (I am not going to go with a chevy rear) I do not want to change the overall length. I have custom offset rims that just came in today, they were sized for the rear that is in the car now. Mistake on my part, was not thinking about the rear at the time? What gear ratio should I be running for this non OD TH350 and engine set-up?
The 8.5 is solid inch wider and also little longer snout so driveshaft will be further in the trans, good street gear with 26in rubber would be 323 to 355, id just gear and posi the 8.2 spend around 1000 including labor in my neck of the woods anyway
YAh that seems pretty high for a rebuild of yours UNLESS they are unfamiliar with the rear and it worries them so they jacked the price up. We can do a complete10 bolt 8.5 gm housing, Moser 30 spline axled, true trac / Eaton/Auburn posi, gear choice housing media blasted primed and painted for 1750.00 ish. Remember that is us even supplying the housing!! Jim J D
I like the sound of that, couple questions though Is the 8.5 a direct bolt in? (no modifications to springs perch, shocks etc. these parts are also all brand new) Will I be able to use all of my new parts? (brakes, drums, hardware, lines, e-brake system etc.)? Are the control arms still compatible with the 8.5 set-up? I am going to put the new rims on at some point today and verify if I will have any issues with the 1'' wider 8.5 rear? What would be the lead time if we start the first week of January?
Tires and rims are on as of today, The rear tires are 275/40/ZR18 with about 3/4 space on the drivers side and about 15/16 on the passenger side. Thinking the tolerences are a little to tight if I try to put the 8.5 in there right now. I would have to modify the wheel house lip and then there would not be any issues. Not willing to do that right now because the car has new paint job. I definitely should have researched this befroe hand. I'm pretty bummed out now. I guess I will have to figure out something for the 8.2 or step the converter down. Tony
No difference in the 10 bolt 8.2 Buick to the 10 bolt 8.5 buick rear. SAME width. all the mounting points are the same. ONLY THING YOU NEED TO CONCERN YOURSELF WITH IS THE DRIVE SHAFT LENGTH. it may need to be shortened you should WAIT to shorten the drive shaft till the rear is installed in the car. then measure the way the shop you are going to have the shortening or drive shaft built at. This way there are no issues on who measured wrong. PLUS you may get lucky and someone replaced the driveshaft in the cars life that put one in too short. I have seen it before. Jim
All my new parts will change right over to the 8.5 rear? The only extra exspence for parts would be pinion yoke, u-joints and driveshaft, is this correct?
Years ago, I went from my original 10 bolt OO code 8.2 to an 8.5 out of a 1971 GS350. What I did was remove the axles from both rears, and unbolt the backing plates with the brakes still attached from my 8.2. I then unbolted the rear from the control arms, removed it, and installed the 8.5 rear. I then attached the backing plates, installed the axles, and I was done without having to mess with the brakes, except for the main rear brake connection. Much easier.
