I have a 59 GMC 1/2 ton and am looking to do a little better highway speed. The truck has the original Spicer 45 with 3.92 gears. I've looked but cannot locate a set of 3.07's for this rear end and also larned from this site that the case may be different anyway. My drum to drum measurement is 62 inches and it is a 6 lug.......any recommendations for a swap that will help? Thanks very much!
I had the same rear in my truck which grenaded one day. I was unable to find many parts available for this after hundreds of phone calls(I spent almost a month looking).What I ended up doing is taking a posi rear from a 1969 chevy truck which is almost exactly the same dimensions and changing the spring perches to match my truck. I have 373 gears in it and have been using it ever since. At the time i wasn't experienced enough at buying used parts and knowing what to look for,and I got overcharged for a rear that needed rebuilding. I wouldn't have minded except that I paid 500 bucks for it to start with. Look close at internal wear if someone wants to charge you much
Thanks very much for the response and advice! I too have made a bunch of calls with no luck and am worried about finding replacement parts. Did you have to change the driveshaft length and did the parking brake hook up ok?
80's camaro,firebird and trans am use the same width rear end; they have disc brakes and different gear ratios are readily available. They are five lug axles though, which is good if you plan on converting to five lug. The origonal p-brake cables are not compatible with any thing other than those year chevys.
parking brake The parking brake did not hook up ok. My talented brother remanufactured the ends of my original brake cables so they would match. He is very experienced,and he said that somebody could make them up at a cable shop. His work pretty good though.
hello I have a 56 3100 and changed the rear in it,I used a 1978 K5 blazer rear which gave me a 12 bolt posi which most of them are because of the 4x4 and it has the 6 lug axles which I wanted to keep,it also had 3.08 gears great cruiseing on the highway! same ujoints as the original, 59 1/2 inches wide,I modifidy the k5 spring perches to use my trucks hardware and I also installed rear disc brakes but the drum brakes that came on the k5 rear worked fine. this setup gives me a highway mileage of 23mpg at 70 mph with a 477 cu in motor and a street tire 1/4 mile of 13 flat at 109 mph so this swap is sturdy and reliable and you can get parts for it easy if needed and they are a cheap buy at most salvage yards I paid 150.00 for mine and installed it,been driving ever since
Hi this is another thought I know that a S10 5 spd trans is very easy swap,it would keep you from haveing to fabricate parts for a rear end swap and do what you are looking to do,a lower final drive ratio
rear end What ever you do do not put a 93-2002 CAMARO rear end in because they are JUNK!!I used a 78 cadillac deville disk posi rear end with a 8.5 ring gear with 308's and it handles my 500 horse 383 no prob.The cadillac rear ends are the same as the trucks because they are so heavy but with taller gears.Hope it helps.
