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

I want to improve highway speed on my '54 3100. it seems it's geared real low, for hauling hay and pulling out tree stumps! what's a typical swap for this truck (camaro?), and what's a ballpark estimate on what you guys have spent for a job like this. really appreciate it, everyone.

I was going to go with a 77 camaro z-28 with 3:42 gears and it being posi, but opted for a 83 K-5 Blazer posi rear with 3:07 gears. Pretty straight forward swap. I went with the blazer so I didn't have to monkey with 6 lugs up front and 5 lugs in the rear. The Blazer has 6 lugs, the camaro 5 lugs. I got the camaro rear end for 150 and the blazer for 75. In all cost will be about $400 finished.

-Chris

I went with the k5 blazer rear3:07, on my 1951 ,3100 ,best improvement you can do to these trucks . oldnavy 51......................

Chris, or Old Navy, when you swapped out to this rearend, did you also open up the driveline? Are your trucks updated with a modern V8, and auto trans.?
KT

When I changed the rear I also installed a saginaw four speed from a camaro,with a hurst shifter from patricks. I used a chevelle drive shift with the blazer rear ,the truck is a lot more driveable now and can be used for daily transportation on highways etc .old navy 51........

I am also running a 1954 ,235,with split exhaust from kanas kustoms and duel pipes with flow masters,being installed today, old navy 51..............

I bought a '73 Chevelle wagon for $10 and used the 3.08 rear from it.

By time I paid for spring pads and having them welded in place, had the drums turned and replaced the various brake parts, and bought 5-lug wheels, I think I spent $6-700 on the project.

Mine is a '55 1st so it was already open drive and I'm still using the original SM 420. Its been three years and I've been almost 100% happy with the swap.

I say almost because it sure doesn't pull a loaded trailer with the same finesse it once did.

10 or 12 bolt chevy or GM rear end is a good start. mounting kits are available from http://www.chassisengineeringinc.com/chevy/1937-1954chevpu.htm
BUT they have a kit that is about 135.00 for the weld on brackets after you have got the 10-12 bolt r-end. so see chevy duty's
'''Our conversion kit allows you to update your existing axle to any 3-inch diameter rear end. Recommend use of early 1970's Camero or Nova rear end. Welding is required. This kit also contains provisions for modern shock absorber mounting.
Part # 93-311 Price Qty $139.95
''' chassiseng'ring makes this product. this kit just makes it easier to do the swap cause the centering of the original axle is off by 1.5'' ... Do your homework and don't just pick something up that's cheap cause you only want to do this once.
SEE:: http://www.smokemup.com/auto_math/index.php go to gearing and plug in your tire size, rear end ratio and calculate your speed @ a given RPM
It ALL depends on the whole package, tranny, engine, engine torque range, rear ratios and what you need it to do. Mine is a 77 chevy 4x4 burb 3.40 rear end 12 bolt w/ the big 2.75''x11' brakes, 6 lugs. my front is 6 lug 10'' disc. I also have a T5 5 speed. the complete rear end completely rebuilt w/ the 3.40 + kit $7-800. then you have to install it and make a driveshaft...

Is it a 1/2-ton, 3/4-ton, or 1-ton truck? That can make a lot of difference in what you do.