VCCA Home Forums TECHNICAL - GENERAL Mechanical - Engine, Trans, etc 1946 1/2 ton Options for differentials

What other differentials will fit (width wise) in my truck? Is there anything that can be done to my 4 speed slider tranny or torque tube driveshaft to improve the speed? I really want to stay with the 6 lug wheel pattern.

Check with mothertrucker@aol.com.

He might be able to help you with a set of 3.55 gears that will fit your existing differential.

he has a good deal on the gears it's the install kit i'm having trouble paying for $395 is the cheapest I can find and is real steep in my opinion . mothertrucker doesn't sale it yet

I was told a Chevy Luv truck had the same width but it's not confirmed ?

Unless I missed something the Chevy Luv is an open driveshaft differential. The cost of the installation kit is a bargain compared to trying to determine how to fit an open driveshaft rear axle to a closed driveshaft transmission.

"The cost of the installation kit is a bargain compared to trying to determine how to fit an open driveshaft rear axle to a closed driveshaft transmission."

Stephen,

A little outside of the box thinking and doing will get you to your desired destination. Here's an example:

https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=882899

I don't know about you but being told that something can't be done or the high dollar solution is the only solution motivates me to be creative. An example was being told that I couldn't change my '36 PU from 4.11 to 3.55 rear gears because the '36 rear axle is spiral bevel and the 3.55 Chevy gears only came in hypoid rear axles. Here's how that "can't be done" project got done:

https://vccachat.org/ubbthreads.php/topics/334876/1936-chevy-3-55-rear-gear-conversion.html

Ray W

$395 plus a set of Mothertrucker gears doesn't sound like much money to me compared to a transmission/driveline/axle swap. Some, or maybe most of the bearings are out of production. Someone must be having them made in small batches. That's expensive. NORS can be found cheaper if you look. You may need to look through old bearing catalogs and interchanges online and then troll ebay for a while.

Or, you could buy a LUV rearend, a transmission similar to yours for open driveline (or do a whole bunch of machine work to the back of yours), Have a driveshaft made (or find a tube the right length in a junkyard, and appropriate yokes, buy some new u-joints, have it balanced), Maybe some rear springs..... It is all real doable, Maybe you can get some of the parts on craigslist. IMHO if you buy smart and carefully over 2 or 3 years, you might get it together for $1200-$1500 with used parts. Maybe less if you have access to a lathe and milling machine and know how to use them. I think $3000 is more likely and if you don't buy smart, the sky is the limit.

LUV axles are 4.10 for manuals or 3.73 for automatics IIRC. Higher gears exist for that axle (used in Isuzu dIesels), but are scarce and expensive. What ratio were you looking for?

i guess it would be expensive to reproduce those parts i wasn't thinking of it that way, i was coparing them to other kits sold and it seemed we are being ripped off because of the fact you can't find them...if i do it i will do the 3.55 gears and kit but i have currently decided to keep my truck like it is and use my perfectly good open trailer to move it long distances ...thanks to you all for all the info

Brino,

Thanks for providing a different perspective on this discussion. I always admire your extensive skill set and thought processes to tackle the more complex tasks.

My comments regarding costs and efforts were intended for those of us who do not have the capabilities and capacities you do.

Keep doing it!

Rusty,

Thanks for the compliment but I was trying to show him that his trans can easily be converted to open drive as described in the Stovebolt information. Street rod builders figure out how to do all kinds of stuff that somehow never occurs to restorers. It may be a different demographic with restorers being more of the "suit" culture and street rod builders being more of the "blue collar" culture, but that's just a guess. Or maybe it's an age thing with younger guys having no interest in learning fabrication skills. I question that theory because my two sons, ages 37 and 39 are both professional engineers and work in offices but they both have mechanical, machining and welding skills that they use in homeowner and hobby tasks.

A common machine shop operation is rear axle narrowing so any rear axle that has a ratio he likes can be narrowed to fit his application. An 8" Ford rear axle from a small vehicle might fit without any modifications except relocating the spring perches and like its big brother the Ford 9" it's a really durable item. Common 8" Ford gear ratios vary from 2.79 to 3.55. Another great choice would be a Ford Explorer axle because it's got disc brakes. Converting those to a 6 lug pattern is another common street rodder modification.

Another option is putting an overdrive on the back of the trans or grafting it into the driveshaft and torque tube. I met a guy with a Ford Model A who had grafted a Volvo overdrive into his driveshaft/torque tube.

The possibilities are endless.

None of the tinkering I do is particularly complicated, just basic machining and welding learned in evening adult education classes. I've met everyone from English teachers to physicians to airline pilots in those classes.

Ray W