Got a '54 Chevy 3/4 ton. Problem is, I want to drive it, and it has a 4.57 rear end. Due to being on a budget(aren't we all), and to keep the truck somewhat original. I'd like to keep the 8 lugs and drums all the way around. I'd like to get a rear end in the 3.56 range. Is it possible to swap the 3/4 ton drive lines into a 1/2 ton rear axle? If not, does anyone know of a rear end that will work for this application, or a 3/4 ton rear with better gearing that will swap in?
I had a 74 Ford half ton 4x4 and needed a 3/4 rear end to haul a big gooseneck trailer. It was an easy swap. Not sure of what is in your truck but there are lots of 3/4 rear ends with higher gears. Swapping them is relatively easy but Fords and Dodges have bigger hubs than some Chevys and you may have to enlarge the center holes on your wheels or use Ford/Dodge wheels. All this info pertains to sixties and seventies but should be the same for your truck.
A rear end from a later Chevy/GMC 3/4 ton with automatic trans will have a more street friendly gear ratio. Don't know of any higher ratio gears that will go into the rear end you have, so you're looking at a trans swap as well and changing to open driveshaft. That 4.57 is great for pulling up stumps, but it winds that old six pretty tight to go more than 45.
Most folks swap in an 8.5" 10-bolt from a 3rd gen Nova/2nd gen Camaro type ch***is. Gear ratios as tall as 2:41 are readily available. These axles are the right width and the only modifications required are spring perch adjustments. Of course you'll end up with a 5 x 4.75 bolt pattern, but you can change that as well.
How can I change it back to 8 lug? Do the drive shafts swap? I'd rather not use adapters, and drums up front with discs in the back just doesn't sound right.
My 2003 Chevy Express 3500 van has 8 lug wheels and 3.73 ratio rear. Might be worth checking out your local pick & pull. You'd have to convert from closed driveshaft to open though. Good luck!
The best gear ratio that will fit the early GM 3/4 ton is 4.11. If you want something else you'll find a later 14 bolt GM 3/4 ton rear from 1973 is about 3-4 inches wider than the stock rear in your truck. Van rears are even wider than a PU truck so measure before you buy!!!. I had a similar truck to yours with a GM 14 bolt and the outside edge of the tires were even with the fenders.You might also consider measuring Dodge and Ford rear axles. Back to the 4.11's ,with a 30 inch tall tire the engine will be about 2700 rpm at 60 mph. That's not bad really.....
i BET that big truck is floor shift & has an open drive, put a T5 overdrive in it. 5 gear would turn 4.57s into 3.08s & 4.57s would be easy on a T5. And some tall tires
Biggest issues you'll find in going with a later rear axle is they'll almost all be too wide. The options are to accept a different bolt pattern and use a common axle that isn't 8 lug. You will probably find your '53 is not an open driveshaft, so your swap might not be simply a rear axle swap. Even if it is an open driveline, and you could find the correct U joint to adapt from one to the other, I doubt you'll find an axle that has the same pinion length, so a driveline change will be in the future. It most likely will be longer or shorter, and possibly a junkyard will provide a factory driveline from something that will fit, but otherwise it means shortening or a new driveline. When I swapped the 464 BBC into my Falcon I found a 1st gen Camaro driveline was exactly the length I needed, and only had to install a TH400 style yoke up front to mate to my Super T10, and an adapter joint out back to mate to the 8.8" Ford rear end.
You could find and install a vintage Brownie, divorced auxilliary transmission. Some of them have a 30% overdrive.
The question is, how do you want to drive it? If it's just a cruiser there's a lot of Ford 8.8s and etc. out there that might work, 3.55 and 3.73 gears, you'd need something to adapt the 5x4.5 bolt pattern to 8x6.5. T5 5-speed is another option and the .63ish fifth would bring cruising revs down. But if you actually use it as a 3/4-ton truck most of the smaller axles that have been suggested - 8.8, 10-bolt, etc - are all semi-floaters and really too light-duty for that application, and the T5 transmission likewise is very weak for that much weight. The junkyards are full of 14-bolt floaters out of just about every 3/4-ton GM product built since the '70s, the drum configuration changed around '90 to make them easier to work on and they grew discs about 2000. Housing and axles would have to be narrowed (those things are so common in Jeepland that you might find off-t******lf axles the right width cheaper) and the spring saddles moved.
If it's open drive, you've got a choice of transmissions. T-5, as already mentioned, the New Process four speed with O/D 4th that was used in '80s Chevy trucks, and even a couple versions of Muncie and Saginaw 3 speeds with electronic O/D that were used from '55 through '71.
It will just be a driver. Might haul some small loads in the bed(household stuff),but nothing like a travel trailer, or boat. After looking around a bit, I think the T5 is the way to go. I can leave the stock rear end, and should make the build a bit easier. Thanks for the info!
I would not put a 1/2 ton axle in a 3/4 ton truck..... 2 very different ch***is. a 1/2 ton chevy uses a 10 bolt rear end. My 1500 express used to eat um.... I got so good at rebuilding, I could do it after work, and new what parts to order ahead of time..... Change your ratio based on ****** and tire size.... I wouldn't go anything p***ed 3:73.... Whats a budget?
Had a '59 Apache 3600 with 4.56 gears in the rear. 55 was my top end. I swapped in a Dana 60 rear out of an '87 Dodge 2500 4x4 truck. Other than moving the spring perches, it bolted right in. 3.55 gears, original 8 lug bolt pattern, and a rear end that's tough as nails. You can also use a rear end out of a mid-90s or earlier 3/4 ton Dodge Van. Same rear, a Dana 60, and they're usually the perfect width (as was the one from the Dodge 2500 I used). I using a "Dodge" rear end bothers you, don't let it. Chevy used the Dana 60 as well, and believe me, NO ONE will be able to tell what it's out of once it's installed. That, in my book, is the easiest swap to do, and the 3.55 gears will allow you to get up to highway speeds while not sacrificing any strength. Chris
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