i have a 1964 Chevy C20 that i'd like to make a little more freeway friendly. would you guys recommend a transmission swap or a rear end swap? what are the pros and cons of each? what kind of price range are we talking? where's a good place to look for them?
Cheapest/easiest is a rear swap. That truck is likely a 4.56 ratio rear, 8 lugs Check with every salvage yard for a late 70s to later 80s fully loaded Suburban 8 lug with the not so common 3.23 rear. It is worth looking for...some pickups had them too. I've done several swaps with those...one is my own that I tow with on the highway. Don't grab the easier to find 3.73, it won't be near as good. You need to cut your perches off and weld them to the new rear, and you need to fab a bracket to hold the panhard bar....or cut a donor bracket off of a 60-63 pickup or suburban.
I agree with F&J that the rear end is the easiest and cheapest. If you do the tranny you obviously need an overdrive and that would require at least a 700R4, or 4L80 if you want "max rugged". The 700R4 would likely be least costly than the 4L80, and also likely easier to find. But you would have rear mount mods, driveshaft mods etc. That would offer the greatest flexibilty though, if you routinely haul heavy loads and could use the lower gearing for those occasions, while still giving a highway friendly top gear. If you present trans is a manual 4 speed, then you have even greater requirements for parts and mods..........so, you be the judge.......but the rear end could be done in a weekend.......vs ????? with the auto conversion. Ray
While it is the strongest of the GM automatics, the 4L80E requires an electronic controller (±$750) and a throttle position sensor (±$235), and harness (±$140) to run it. It does not have a provision for a mechanical speedometer, but a drive box, run by the controller, can be had, but that is several hundred dollars more as well (±$420). All of that is before the cost of the transmission and torque converter. You can build (or have built) a 700R4 that won't break too easily, so long as you don't drive like a goon, or have a 572, or both.
I've got a '63 C10 with the granny 4-speed and a 3.73 rear. I picked up an A833 3speed + OD manual transmission out of a '72 Chevy truck for $200. It'll be installed this winter.
I never heard of it in a 72 Chevy but..... I could be wrong but i thought someone on hamb said that the Mopar designed OD box was used by another car maker.... I just can't remember anything about the thread.
Yep! Chevy bought & used the A833 in a 3-speed w/ OD configuration from NPG from around 1972-1978. There were two different ones: One bolted up to a conventional SBC bell housing and the other had the MOPAR bolt pattern and required the original SBC-MOPAR aluminum bell housing. As far as I know, the rest of the two transmissions were identical to each other.
The codes are stamped on the top of the axle tube. The local yard had a book to tell what code letters meant what ratio. That same yard told me that ratio was easier to find in a Suburban with lots of options ??? I also found one in a 79 3/4 ton 4x4 pickup...that's the set I still run. One axle is 3.21 the other is 3.23/ I am pretty sure the front is the 3.21..
You can convert a 4L80E to plain old hydraulic operation with a TransGo HD3 kit for about $250 and ditch all the electronic crap. That makes the idea of swapping that trans into an old car a lot more appealing if ya ask me.
It is not an automatic when you go that route. You HAVE to shift it, and those shifts will be HARD. Not ideal for a street vehicle.
I thought that was an early-mid 80s thing. If you can find one, it would be a reasonable way to go. Brad54 on here (Brad Ocock in the magazines) has been playing with them some too.
"I thought that was an early-mid 80s thing." Squirrel, you're correct - my old brain was off a decade. I checked my information and the A833 w/ OD was used from around 1980-1986. Mine was off an '82 pickup, not a '72. Sorry for the mis-info.
The Jalopy Journal
