The Stovebolt Site Forums The Shop Area Driveline T5 Tranny Swap 53 1/2 ton

hello all

I am thinking about swapping my 3 speed on the tree for a T5 tranny that has already been equiped to fit onto my 235ci engine. my question is the back half. i have an enclosed drive shaft and the original rear end. can anyone tell me if i could run this set up with my rear end or would i have to chunk it all? how would a t5 bolt up to my driveshaft? i can pick up the tranny for about $300 but if im gonna have to spend alot more making it work ill stick with the 3 speed. Pics would be great. i have minimal driveline experience so please simplify

You need to get the center section out of a 55-62 1/2 ton & replace yours in the original houseing. Set the pinion angle & weld the pivots by the springs so they won't turn. Get the drive shaft from the donor rear end & a front yoke to match the trans. Have a driveshaft shop put them together & shorten the shaft to the correct lenght. They really arn't too hard to do mainly because there is so much info out there. See the Tech tips & do a search. Ask any questions on this website. A lot of us have done them & the results are rewarding. Bowtie tim has done 2 on those models. The ones i've done have been the later model where I didn't have to change rear ends.

Great advice above. As he says you'll have to bite the bullet for the change to overdrive transmissions. First make sure your brakes are 100% before contemplating more speed, if you're already there that is half the battle, IMHO. I did exactly as Wrenchbender suggested by pulling out my center section and eliminating the torque tube for the open drive shaft and 3.90 conversion. As below in my signature 55k miles, daily driver only vehicle. Keep asking questions, a lot of us have been where you are.

didnt think of that option. howevever this brings about 2 more questions

1- wouldnt it just be easier to replace the whole rearend and remount the leaf spring mounts than gutting the rear end

2- this would still leave me with the 6 lug pattern? i would like to have 5 lug so i can update with more modern wheels.

i spoke with someone last night about replacing the rear with a late model rear end and that seems like a doable task on a weekend in my garage. i think later model rears would be more easy to come by than 55-62 chevys?

thanks for the help

If you put a much later rear under it, you will have bigger brakes in the rear than in the front and they will lock up first, especially on wet pavement. It has been done, but there are a lot of changes in putting overslung springs instead of underslung springs in the rear. The simple way is the way wrenchbender describes and a 3.90 with an OD in front of it is very driveable.

cant i just cut off the spring mounts off of my old axle and weld them onto the new one?

"cant i just cut off the spring mounts off of my old axle and weld them onto the new one?"

NO! The spring mounts you have are inadequate for an open driveline. You could get Mopar spring pads at your flaps for less than $30 a pair to weld on to the donor axle. Many of the parts suppliers for our trucks have a rear axle installation kit that usually comes with spring perches and u bolts. You will have to check closely to see if they also come with the shock mount.

Many different rears have been used, there isn't any that are really favored. If you want 5 lugs, maybe try a camaro rear. I don't see how 5 lug would be an update, and modern wheels are ugly as hell! But hey, if that's what you want... go for it!

1.You will need to drill out the transmission mounting holes(4) with a 1/2" drill bit.

2.Cut the tip of the transmission input pilot shaft down"I believe 1/2" " be sure to measure your original one.

3.The clutch gear bearing retainer will need shortened to the length of the original one.I believe it will be about 1 1/4" cut off of the retainer"the place where the throwout bearing rides".Be sure to do your own measuring and comparing.

4.you will have to extend the splines on the input shaft about 1/4" to 3/8" longer.I used a hand held die grinder to do mine.

The non-world class t-5 will have a 14 spline input shaft.This means you will need a 14 spline clutch disc and use the original style pressure plate.Measure your original clutch disc and I'm sure we can come up with a part number for the new clutch disc.

You will use the original bellhousing and clutch linkage with this swap.The only thing different will be the t-5 and the clutch disc.

I wouldn't use the 3:08,the 235 will struggle with it.I'm thinking 3:55 or 3:73 ring and pinion gears will be what you want.I have a 3:90 in my suburban,but it's a tank and a 3:73 in my truck.Make sure you read about the proper pinion angle setup .

You will need to have a drive shaft built for it,and you will need to measure for it correctly.


Tim

Do what bigdaddy says,buy the perches and weld them on the rearend you choose to use.I understand you have more wheels to choose from when using a five lug pattern.

55-62 pumpkins and rearends are plentyful,should be easy finding one.

Good luck,
Tim