The Stovebolt Site Forums The Shop Area Engine Shop 53 with a 55.1open driveline and rear axel??

What better place to ask than the stovebolt.

I have a 54 possibly 55 1st (open) drive line and rear axle. This is from a GMC Hydromatic (engine and tranny are gone).

I was wondering if I would be able to adapt it to a 235 with a 3spd trany?
What advantages or disadvantages are there?
I do not know the gear ratio for the automatic rear end.
Would this combination work, especialy during highway driving?

Would a 4spd trany work better for this?
This is for my 53 1/2ton.
[img]http://shutter15.pictures.aol.com/d...h7xls-i5SdVmVqqSKLJiNfL2AK7UBxL40060.jpg[/img]

Any advice.
Thanks in advanced for your replies.
Javier

I am unable to enlarge your photo but it appears to have a split windshield which makes it a 53 or earlier. Try posting a link to the photos you have.

Yes it can be adapted to your 53. The rear end is likely a 3.90 gear ratio. I did the same thing with my 53. I also installed a over drive transmission which helps tremendisly on the highway. It is a bolt up installation.
Tom

OOOPS, I reread your post and see that you state it is a 53. My error. That is what happens when you respond after two large margueritas. :o

Something to be aware of; the springs for the closed drive shaft trucks have the center bolt in a different place than the open drive trucks. Therefore you will have to make a locator plate to compensate for the difference. That is unless you also have the springs for the 55.1 truck.

The gear ratio for a hydro truck is 3.90, the same as a 54 & 55.1 truck.

Just drill a new hole in the spring 1 1/2" to the rear and install a new locator bolt(available at a spring repair shop). Then remove the original locator bolt and install the 55.1 rear end. Leaving the old locator bolt"in" untill new locator bolt is installed keeps the spring together.

Would there be some kind of adapter needed between the open drive line from the 55.1 (gmc) hydro to the stock (chevy) 3spd trany.
Would'nt there be some type of fluid leak?
If there is such an adapter who would make it?
Also, if I was to change the trany to a 350 4spd or like, What type of adapter plate would be needed between it and the 235?
Who would have that?

All your info is helping. This is my first engine,trany and axle swap.
I like to keep things basic and as original and old school as possible.
At first I was going to attempt the S10 and nissan axle but I think this will still keep me with the old parts.

Thanks Again
Javier

Not that I know of, you need to change you tranny aswell.
There is a tranny adapter plate to mount a T350 behind the 235, I beleive buffalo enterprises makes it...do a search. A good tranny would be a T5, also do a search and you'll find lots of info.

Good Luck

I have fitted a '56 open diff to my '40 , keeping the original 4spd box.

An adaptor/seal holder needed to be made for the rear of the 4spd. Not a big deal for someone with a lathe. And , of course , the front yoke needs to be modified to fit the 4spd splines etc.

I mounted the diff using the original spring center bolt . I moved the diff back a little till the front hole in the mount plate lined up ( there are 3 cavities in my original mount , the proper centering hole , and 2 casting relief holes ) . It is not a tight fit on the spring bolt , but is OK as it has been there for over 50,000 miles now.

The center section from the 55 should bolt right into the rear axle carrier from your 53. All that would be required then is to weld the swivel points on your spring perches so that the rear axle doesn't rotate on the spring as it does now with the torque tube driveshaft.
There is a member on this site who did the conversion and took a lot of excellent photographs showing it all.
Bill

Does anyone know who this member might be?

Dusty,

I have been toying with the idea of converting my closed drive to an open drive. I have a hydro and not sure I can find another trans or find the parts to convert mine to an open drive.

Will you discribe the work you did to close your 4 spd. and run an open drive shaft. If you can draw a sketch of what you did I would love to see it. You can email me or send my a PM if you would like.

Did you eliminate the U-joint in the trans, and run the front yoke of the drive shaft on the rear main shaft of the trans? What was the mods that were made to the yoke? What yoke did you use?

Thanks.

RaNfLaS,
I think Bill is refering to Steppenwood pumpkin swap.

Tell me if the link works.

I've done the conversion from closed to open driveshaft on my 54 AD. The closed diff to open diff conversion and to relocate the open diff. to center the wheel in the wheel well, requires nothing more than a 6" piece of 1/2" thick X 2" wide flat stock. I drilled a hole on the bottom of the plate that fits over the stock spring pack bolt head and then went 1-1/4" back from that hole, on the top of the plate, drilled and tapped a 5/16" hole, locktited in a bolt that fits inside the center hole on the mount plate on your open diff. This moves the diff back to center the wheel in the wheel well, and when you u-bolt it all together it sandwiches the plate. I also removed one lower leaf from the spring pack. I could/should have gone with a thicker plate to lower the stance on the rear axle. I've got some 1" thick plate which I will weld to the 1/2" plate. At the time my u-bolts were too short so I got in a hurry and only went 1/2" thick.

I found that Autozone has a "lowering kit for the longer u-bolts....you don't want to use their flimsy aluminum block. One word of caution....don't do anything about your driveshaft until you've got your diff all secured. Moving the diff to the rear 1-1/4" does NOT equate to adding 1-1/4" to your shaft. Not quite sure why, but WAIT UNTIL EVERYTHING IS BOLTED UP, WITH FULL TRUCK WEIGHT ON YOUR SPRINGS TO MEASURE YOUR DRIVESHAFT.

I've got some pictures of the conversion on page 6 or 7 of my webshots "shoebox". The full cost of the materials for this conversion were $24. for the AZ lowering kit and a couple bucks for the plate. I used the stock shock mounts and u-bolts from the original diff.(no modification needed) Installation took me a couple hours. I retorqued the u-bolts after a couple hundred miles...works like a charm at 1/4 the price of a mail-order relocation kit. Hope this helps.

Colin is right. I was referring to him. I have all his photos because I think he did a great job and will probably do mine sometime. Sorry I forgot his name but I was typing as my office was filling up with flood water and I was rushing to get out.

I would like to thank all of you for the great information you provided me.
I was a little intimidated at first, but now I feel every bit confident that I could accomplish this step of my 53 project.

Thanks again
Javier

Good for you and good luck. When you are finished you could come and put all that experience into play and do mine. I'm too timid to try it myself!