The Stovebolt Site Forums The Shop Area Driveline 58 chevy apache trans question

I have a 58 chevy stepside shortbed, original 6cyl, and 3spd trans, it tops out close to 50mph, i was told i can put a S10 5speed trans in my truck, will this fit? and then i can drive on highway. will appreciate any help,

You can find some info on the tech section of Stovebolt about T5 swaps, mostly for AD trucks but good info. You can also find info on other websites like http://www.inliners.org/
You'll get overdrive with the t5 which will be a big help. I haven't done it but I plan to some day.

There is oodles of info on this website about this popular swap. Like Nar says look at the Tech tips. Do a search as there have been many threads about this. If you have any questions post them. I have done 3 of them & Bowtietim has done 2. There are many others active on this website that have done this. We are all glad to help. The results are fantastic.

That truck should be able to do 70 mph all day at 3000 rpm. If it can not get up over 50 perhaps you have the wrong rear axle in there, or are missing a gear.

Here are the obvious questions.

How many lugs do your rear wheels have?
Does your transmission have a floor shifter or is it a column shifter?

yes, what ^ daddy says, a stock shortbed [1/2T] should have a 3.90 rear ratio and should do 70 in high gear - do you have the gas pedal to the floor at 50? or maybe you think it 'tops out' because of the sound?

Bill

My truck has the stock rear end
has 6 lug wheels,
it is not floored at 50mph, it is just roaring and sounding like it is topping out.

my truck is the original six with floor starter,
can you tell me what transmission is best and what modifications i will need to have done to complete its installation

You might want to consider a 3.38:1 gear set from Patrick's. Not as much help as OD but it would be an improvement. While you're at it you could put on one of the shiny chrome differential covers. At least if you're holding up traffic they'd have something pretty to look at.

http://patricksantiquecars.com/chevy_parts.html

Sure it's not 4.11?

An overdrive allows normal gearing until cruise speed , necessary if you have a load on board or are towing .

A taller gear ratio will affect the pulling capability of the original engine that you have , especially on hills , even when unloaded.

Your standard diff ratio is 3.9 , if it sounds too busy , you might like to try removing the big fan blade and installing an electric unit as a test for sound comfort.
If it is still very busy , it may be the old engine is getting a bit loose and no amount of gearing will fix that.

Just found out my 58 chevy truck has a 58 gmc 270 engine , will the t-5 transmission still work for me?

lancer, it'd be a job to fit a 270 into a Chevy frame, how did you determine that? give us some numbers [block casting and/or stamped number on pad by dist] ... what trans will fit would depend on what was done to install that 270, especially with respect to where the floor shift winds up

Bill

The Chevy and GMC bellhousings are similar, so the same process of adapting the T-5 will work with either engine. Lots of Chevy/GMC engine swaps have done in the past 60-something years so it's not uncommon to find a GMC engine in a Chevy. Basically a GMC is about 2" longer and needs some front motor mount and radiator position modifications.
Jerry

Far as I can tell, stock GMC could be had with 3 sp SM318, 3 sp SM320 (T85) or a 4sp SM420. (or a "Hydro"). Some of these transmission depend on if it was a 6 or 8. I believe all these were offered by Chevy, That means the bell housing should fit a Chevy engine as has been said. Don't know if a T5 fits where those trannys fit. Probably does. It does not mean input and output splines/shafts will work with whatever you are doing. It is possible that they were different for GMC vs Chevy. Starter mounting and flywheel need to be studied also depending on if you switch bell housings and trannies around with a 270. Just do your homework and take it all apart and be sure what you have or post pics of what you have or numbers.