The Stovebolt Site Forums The Shop Area Engine Shop 54 Chevy P/U-Rear End Questions

I have a 54 Chevy 3100 Truck, all stock, which the 235 I6 just gave out. Before I decide what to do with the motor or what is going to replace it, I have questions about what someone might recommend to do with the stock rear end, which i believe is a 4.10. With the stock motor it could barely do 55 on the road, I'd like to get something that will be a little better for driving than that if i'm going to put any money into the motor.

Questions:

Is it worth changing out the ring and pinion gears to change the ratio and leave it stock otherwise?

Are there other rearends which are readily available that could be put in that will install relatively easy (ie not narrowing it)?

Are there rearends that would fit and I could keep the 6 lug pattern?

thanks, in advance for any help.
aric

Hy Onelane, Welcome, there are other ratios available from the restoration vendors, and the 55b-59 differential is a direct bolt in [3.90-1]. Taller tires will also give you more speed. Hope that helps.

The spring hangers, u-joints, etc are a bit different since the '54 is a closed driveline whereas the '55 and up is a open driveshaft.

For a direct bolt in, you would need the tranny, springs, rear axle and driveshaft from a '55 1st Series. Never done it myself so there might be a few more gotcha's to contend with.

The stock '54 1/2 ton has 3.90 gears.

Hi onelane welcome to the Stovebolt. I think I gave you my answers to this on the HAMB...

oldsub, thanks, yes same post as there. someone recommended trying this site too.

This stuff is all so new to me, I need all the help I can get. I've got some good friends who are much more mechanically knowledgeable, but none who have really dealt specifically with an old truck like this, and it's quirks... appreciate all the input i can get.

aric

If the 54 rear axle is the same as earlier AD trucks you can use the centre section of a 55 and up rear simply by bolting the ring and pinion in. Use the same housing, axles, bearings, etc. The only thing is you would have to weld up the spring/axle pivot points. One of our members 'steppenwood' documented it very nicely with photos.

Onelane, the 55 1st rear end is a direct bolt in. I used one on my 53. You would be ahead of the game to install a overdrive transmission at the same time. I did and I can run at 65 and 70 on the high way with my 235 just like the big boys.
Tom.

welcome
this is a very popular subject and has been round n round. learn to do searches see upper right corner under new posting button.

see

http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=5;t=001398;p=1#000008

http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=2;t=013343;p=1#000002

thanks for all the info. sorry,i didnt think that would be such a popular question.

as far as the trans goes, i've heard mention of 3spd with OD and 4 speeds. Im trying to keep the column shift, is the OD something that can be added to my current 3spd trans, or is it a whole other trans and what kind of vehicle could i find one from. and where the 4spd on column common? My trans works just fine, but having another gear or od would be nice. as i live in a rural area and all the roads around here mostly 55mph. im not in a lot of congested town traffic.

The overdrive trans is a different unit, you can find them relatively easily. You will need one from a '55 or later car or truck (either will work), those will use the original column shifter. You will need to make sure to fet one that has the same lever positons on the tranny as your original, the '55-'56 6 cylinder trucks are slightly different, but can be altered.
No 4 speed column shifts on Chevy trucks, exept for some early Corvair Greenbriars, and those don't interchange.

thank you.

Bill, how does the overdrive work? is it an electric od, is there a button to engage the od, or is it an extra shift? thanks.

are you trying to keep it stock? if you are just rebuild the motor. if not the sky is the limit! or rather your wallet. seems to me going to 5-lug will give you "unlimited" rearend ratio's, staying with 6-lug and finding a rearend the correct width severely limits the choices. overdrive or t-5 are good choices. keep asking questions and get familiar with the "search fuction". good luck!

The overdrive used in the old trucks was an electrically operated unit, essentially a 2 speed planetary gearset. In the original applications, it was on when the ignition switch was on, the activation was controlled by both the governor (cut in about 28 mph) and a lockout cable that would prvent engagement when not desired. Here's a link to the manual describing the operation. http://chevy.tocmp.com/1955truck2shop/55ctsm0716.htm
I have mine on a separate switch, so it's only on when I need it.

Thanks, that will help.

Does anyone know if a 5 lug version or something similar to the stock 16" rim is available? I'd be looking to use the tires from the 6 lug stock steelies ihave now. I'm not sure how wide the rim is, but it is pretty narrow. thanks