Rear end parts most dont think of

[BarryGMC]

Being a Jeep nut and old truck crazy has given me some unique perspectives on how to improve/modify our old stuff without going broke in the process. Dont get me wrong on preserving nice original rigs. I will search the world over for the proper parts for my 58 impalla or the cad. I even will on some of the trucks. However Most of the trucks do get used for work year-round. Its to much fun to get 2 units of ply in a 37 chevy 1-1/2 ton or 40 sheets of firerock in a 65 gmc. People say I am crazy but its no fun to just look at them. So here are a few things that I have found that work in our old GMC trucks that wont break the bank, and make our driver trucks more roadworthy. First 90's Ford and Dodge one ton vans with the D60 are a great place to find 3.54 third members. Carrier and all are 45.00 here in the pick and pull yards. So for about a Ben Franklin you can get on the road with some highway friendly gears in your 1500 truck. If you have 4.56 gears look under a 70's GM 1/2 ton for a stewart warner ratio adjuster with the 1.22-1 # on it, 4.09 need the 1.1 or 1.3 both work well. those are 2 bucks here. Second is easier with a K1000 than a 2 wheel drive but if you do a disk brake conversion on the front this would work also. So you have a K truck with axle troubles and bad brakes we all know about the 70's front axle conversion. Disk brakes open knuckle....For the rear use an Izusu rodeo/Honda passport D44. It has disk brakes. Usually a trac lock 3 series carrier with a thick 4.09 ring gear and six bolt axles. These are 95.00 in the pick and pull yards. These are 1/2 inch narrower than the stock D44 in our GMC's . I have never spent more than 500.00 on this swap on a k1000. And 100.00 was on an adjustable brake proportioning valve. Keep on thinkin.... Barry Charon

[FetchMeAPepsi]

Originally Posted by BarryGMC

... If you have 4.56 gears look under a 70's GM 1/2 ton for a stewart warner ratio adjuster with the 1.22-1 # on it, 4.09 need the 1.1 or 1.3 both work well.

Thanks for this Barry. So if I read that right (needs paragraphs!) then on my 4wd if I want to go with highway gears I just need to check out a 1970-1979 Chevy or GMC 1/2 ton truck.

I'd be looking for a Stewart Warner Ratio Adjuster. If it has a 1.22-1 on it then I'm good to swap and it won't blow up my 4wd front gears?

[BarryGMC]

The ratio adjuster is for the speedo. You still need to match the gears. Sorry about the writing math was my thing. BC

[BarryGMC]

IS your truck a 1/2 or 3/4 ton

[FetchMeAPepsi]

It's a half ton with the 305 in her. I'll copy over my build thread later.
Don't worry about the math thing. If not for guys like you we'd never figure this stuff out. I wish math was my thing.

[BarryGMC]

71-77 are the best for a straight axle conversion disk front d44 and 12 bolt rear. However I dont like the 10/12 bolt gm axles. I prefer the Dana stuff and with the disk brake rear I love the Isuzu/ Honda D44

[bigblockv6]

I'll take a Dana 44 any day,GM 10&12bolts are pure junk. Pete Chronis
Northern Cal.

[BarryGMC]

Better axle bearings, carrier selection, and no c clips. also the 12 bolt cant handle the torque of a 4x4 in low range. Crush sleeve loosens up under high torque and rear dies.....

[TimC]

What about C-2500's? I got Dana 60 w/4.10 (ugh!). I belive 3.54 is as low(high) as I can go. Is anybody aware of something other than all new parts that will work in the 3/4 ton trucks? ie any crossovers I can look for in the pick a part yards?

[raycow]

Originally Posted by TimC

I belive 3.54 is as low(high) as I can go. Is anybody aware of something other than all new parts that will work in the 3/4 ton trucks? ie any crossovers I can look for in the pick a part yards?

Are you saying that you want taller gears than 3.54? If yes, you have a few possibilities. One would be an overdrive transmission, either manual or automatic, depending on what you have now. A Gear Vendors O/D is available for the GM 4 speed manuals as well as the automatics, but an overdrive automatic would likely cost less than the GV.

Another fairly easy swap is the GM 14 bolt axle, which I believe is available down to 3.23. Lastly, in the 1960s, Mopar used a D60 in some of their high performance cars (like Hemis). I don't know if that one was available with taller gears than 3.54, but in any case it would probably be a collectors' item and priced accordingly.

Ray