The Stovebolt Site Forums The Shop Area Engine Shop rear end ?

i have a 56 1/2 ton that has 5 lug front and 6 lug rear, that is how it was when i started driving it 20 years ago, ready to match rear end to 5 lug to simplify things,i have updated to disc on front, which rear end would be the best/easiest fit,was told 71-80 camaro, thought about rebuilding the rear end with a 338 ratio but having trouble locating 5 lug axles, any input good or bad will help
stephen

I put a gm 8.5 inch 10 bolt in my 58 out of a 76 Nova. I didn't ask anyone here about it but took the advice of a guy that claimed it was a perfect fit. It wasn't, live and learn. The Nova rear is 60 inches wide and would probably fit the AD model perfectly, it is a bit narrow for the TF models. The 1967 12 bolt truck rear I took out of the 58 Suburban was 62 inches wide and had 235/70-15 rear tires that fit in the wheel wells nicely. My options to make the Nova rear fit were custom offset wheels or longer studs and spacers. I went with the spacers but will eventually replace the rear with a wider one. Fortunately the Nova rear will be a good fit for my 64 El Camino. Bottom line is I think you need to look for a rear that is about 62 inches wide at the outside edge of the axle flange/brake drum. If I remember right, the 71-80 Camaro is that size, earlier Camaros were narrower like the Nova rear I have. If you are running stock rear springs you will need to replace axle pads on the Camaro rear.

The 8.5 inch 10 bolt is a good rear end. Mine is running a posi gear carrier out of a mid-80s truck with a 3.42 gear, after-market 31 spline axles (12 bolt Camaro application), and a new bearing kit. Compressing the crush sleeve was a huge pain and getting the shims right took a dozen attempts (or more) but otherwise the rebuild wasn't bad. Local auto parts store let me borrow the tool kit needed to change all the bearings. I'll probably buy a cheap pinion depth setting tool before doing another setup.

good sounding info
thanks

I've found the 3rd generation Camaro diffs at 62" from wheel mounting surface to wheel mounting surface work well in the AD truck and should be applicable to the later models. These diffs are most commonly found in a 3.08 and 3.42 R&P ratio. The 3.73 ratio was also available but not as common as the 3.42 from behind the 2.8L V6 in the automatic cars.

Being a coil spring diff you'll need to burn/grind off a bunch of the mounting brackets and weld on your leaf spring perches. The Camaro emergency brake cables can be slightly modified (turn-buckle & cable clamps) to tie in with the stock truck emergency cables. In addition, the Camaro rear sway bar can be flipped from the bottom of the diff to the top, using only the Camaro hardware, and will bolt up to the frame requiring only 2 holes to be drilled. If by chance you're running a T5 transmission the S10 short bed driveshaft can be bolted in without shortening or modifying the U-joints. I've used both the drum brake setup from an 88 and also a posi/disc from an 89 IROC-Z. The "Z" diff has some drawbacks as axle seals for these Australian Borg Warner units are almost impossible to obtain.

The advantages of using the Camaro diff are that they are 5 on 4-3/4 bolt pattern, the correct width to center the wheels in the wheel wells, most times lower mileage, with swaybar/emergency brakes adaptable and the best part is that they normally sell for $100-150.00.

The only negative I've found is that you'll need 3-1/2 to 4" backspacing on a 15X7 or 8" rim and if you're running a disc conversion on the front, that backspacing will clear both the stock and upgraded tie rod ends with 235/70/15 tires. Not many salvage yard rims available in that combination.

Dave

i think the camaro will be my best opt., just need to start looking,i have a turbo 350 now but looking to get a overdrive transmission, i drive about 70 miles one way to work,that 305 turns a lot of rpm's at 75mph

The TH200R4 is the same dimensions as your TH350 and comes with a universal GM mounting pattern (both Chev and BOPC). the 700R4 is a bit longer.

thanks for info