The Stovebolt Site Forums The Shop Area Driveline ANOTHER REAR END GEARING POST (47-54 TRUCKS)

I have a 235 in my 51 and the original torque tube, and 4:11 gearing. Im not wanting a streetrod as I bought this truck because its a stovebolt and period looking.

like everyone else Im wanting to change to a 3:55 gear.
the 3:55 install kit and the ring n pinion are over $900 combined and I am not comfortable doing the swap myself based on what Im reading needs to be done.THIS IS A BIG JOB!
PARTS AND LABOR IM LOOKING BETWEEN 1700 AND 1900 INSTALLED.

I am curious what my options are. I do not want to run a T5 my origianl trans 3speed on column works great and shifts like butter.

I do not want an S10 frame if I did I would have bought anS10 truck.

I have heard of using early 50's powerglide car rears due to the factory 3:55 gear and torque tube on 46 and older truck but what are the alternatives for the AD trucks.
thanks

If you figure out a less expensive alternative, let us know. An alternative that includes new internals, seals, and bearings and labor.

Luckily, I saved on labor - I had a friend with me - he knew modern rear ends. We figured out the old torque-tube and it runs like a charm (check the Stovebolt Tech Tip by Sweet). I bought the tools I needed (run-out gauge and magnetic base holder?) from Harbor Freight. Prussian Blue "grease" is readily available (Permatex).

You can buy taller tires. What are you running now?

passing thru,

There is someone on Ebay selling the rear ends with the replacement gearing installed as John Millman, Denny Graham and Chris Sweet and Barry Charon said in their missive. They mention "not including" the brake drums"
I cannot find them at this point. I'll guess someone bought them or they timed out.

Julian

There are several obstacles to overcome with the car to truck swap:
Different spring spacing
5 lug axle shafts that do not swap with the truck 6 lug axles
Different torque tube and driveshaft length
Possibly different U joint

By the time you get the car axle adapted, you'll have a great deal of money invested in a non-original item with virtually no source for repair parts if it gives trouble later. Do your homework before beginning that project. Where in Georgia are you? I'm in middle Tennessee near I-65 and the Ala/Tenn state line. I have a complete 1952 Powerglide rear axle assembly stashed away.
Jerry

A Task Force '55-'59 3.90 rear differential or the entire axle for that matter will give you easy 65-70 mph w/o taxing the engine. I routinely go over 2000 ft passes in 3rd gear with my 3.90 rear in a '49 1/2 ton.

The engine is a '56 235. I've bought 3.90 rears for $125, 20 years ago and as recently as last year.

What Cosmo said 110%. Get a donor truck 6 lug diff 55-72 with what ratio you like. Get a driveshaft with it and get it modified. Get rid of Torque tube. Go open. Then if anything goes wrong, the parts are easier to find, install and more reliable. Way cheaper and DIY. Just study google and here for what diff has near WMS-WMS and what it takes at tranny. Lots have done it, lots of info. You can buy 10 diffs for that money.
If Cosmo says 3.90 works, he knows. I would go higher, which is a lower number.
BTW I have a nice 1953 AMI 120E.

Thanks Bart. Here in the Piedmont (rolling foothills) inclusive of 2000 ft passes to get to another valley the 3.90 happens to work well. You live in GA, so consider the terrain where you will be doing most of your driving and the speed with which you would like to travel. I'm with Bart's advice about getting out of the torque tube for the main reason of the availability of overdrive transmissions. I have a '69 3sp+od with 3 on the tree and love it! Prior to this transmission I had the earlier generation 3 sp+od the series with the non-synchro first gear. I ran that transmission for near 15 years, 3 on the tree, loved the capability.

You can have what you desire, column shift and good drivability, even without an overdrive..

Other options:
In 54 trucks had open drive shafts with a drop out diff. All the way to 62. 47-53 has a Torque Tube drop out. You can swap guts/drop out and make a TT rear end into a open. It's a bit of a fab intensive job but not real technical. That gives you ratio opportunities, stock diff/width, No brake line or ebrake cable problems.
Basically: Take off leaf spring to axle tube "clamp" and weld on a spring perch on bottom.

1954 trucks larger than the 3100s had open drive shafts.
1954 3100s had enclosed driveshafts (and 3.90 rear ends).

Doesn't a 51 3 speed have the oddball small transmission to bellhousing bolt pattern? If he's going to swap to an open driveline he's going to need to change everything from the engine back, including the bellhousing. Looking at things from that perspective, the 3.55 aftermarket gearset begins to look a lot more budget-friendly. Granted, us old geezers who aren't intimidated by setting up rear end gearing are getting a little scarce, but it's not impossible to do.
Jerry

Thanks TC, I'm off a year or two. 55.1 have open on 1/2? or was it not until 55.2?
Anyway Jerry and passinthru: I did my 60 diff awhile back. I don't know yet if I did a good job or not. I think so. This poster seems like not ready to try. It took me till now to get the nerve.
In my case I had to buy:
1. Torque wrench that went to 250 lbs. I only had a 150
2. Inch pound torque wrench
3. Dial indicator and magnetic stand
4. Build a yoke holder
5. 20 T press
6. Two sets of pinion bearings
7. Two sets of carrier bearings
8. Ring and pinion gears
9. Shim set/yellow pattern compound
10. One set Spyder gears
11. New pinion nut
12. One set wheel bearings and retainers
13. Seals
14. Gaskets
15. Grease and oil

And:
Heaving lifting, took off diff and put on bench
Drill and split old wheel brg retainer
Old parts and bolts put up a fight and must cut off/heated/etc. sometimes.
I'll bet AD parts will be harder to find than my era.
Room to work/high bench preferred
Lots of tools
Total cost of parts and tools= cheaper than a shop and I keep all the tools/equipment I bought.
I tried for 4 months to find a donor GMC Dana 44 in 3.92 to match front diff. No dice.

It is a chore. I have a lot of mechanical experience, tools, read up on the technique, and finally, the patients to get it right after many tries.
It ain't rocket science but it ain't changing your oil either. I don't know if AD is easier and needs less equipment or not.
Whatever he has to do up front is just bolting donor parts, I assume. I'm sure several guys will chime in who have done this and it's probably in the search.
I'm basing my advice in this case on the $1900 and the
poster not comfortable doing it. Some cases I would encourage a Stovebolter to go for it DIY and learn. Not in this case with a diff gear change unless somehow there is no need for all the backlash/preload/press off, press on/tooth pattern check procedures.
Even though a person could swap drop outs, that's a lot of work and some welding. I would still recommend a open drive line. A good, patient, searcher/scrounger/negotiator could get the parts for $500-$600 total if in a populated area or lucky enough to be near one of those good old wrecking yards. Now almost all gone.
So that's my story. Good luck, from "Justhanginginthere"

bartamos,

1955-1st was the first 1/2-ton (31xx series) year/model with open drive shaft.

Thank you, correction noted.

Bart, did your kit come with a 'crush sleeve'?

No, there is no crush sleeve on Dana 44. They use shims only. If you buy two sets of bearings, you grind one set to a light press fit and use them on and off until finished shimming for preloads, backlash, pattern and then press/drive the other set on. I did mine because I had a broken pinion, not to change ratio.

Jerry,
I have a '50 3100 which at one time or another, I have had a torque tube 3-speed, a 66 Saginaw 3-speed, and now a T-5 bolted to the original bell housing. The bolt pattern was the same as the original bell housing on all three transmissions.
I am assuming it would be the same fr a '51.
Carl

The 4 bolt Chevy trans pattern is pretty much standardized with a few exceptions., It is the bell housing to motor and starter mounting/flywheel size problems that most encounter. Not relevant in this case. The pattern fits Muncie, Saginaw, Stewart and others. This is just one example why Chevys are used so much in all forms of swaps. Everything fits everything, almost. Fords are not like that at all. You can find Chevy built motors in trucks, cars, boats, motorcycles, military vehicles and planes. (Pratt and Whitney radial engines for bombers and cargo. Every part built and assembled at Tonawanda. WWII.)

In 1948 Chevrolet trucks started this transmission bolt pattern.
In 1955 this same pattern was started in passenger cars.
This bolt pattern was used for as long as I have knowledge of, may still be used.
It is also the same bolt pattern the T5 trans uses.

OK- - - -I have several torque tube transmissions and a couple of bellhousings with the smaller bolt pattern- - - - -obviously passenger car stuff! Good to know when the change was made!
Jerry

are the 55-59 rear axles the right with etc?
what else is needed to make this setup work?
does the trans have to be modified in any way?
does a 3:90 rear end really make that much of a difference? vs a factory 4:11?

what is a 53 ami 120E?

It's a Jukebox. 1953 AMI 120 songs. I thought you were hip to Jukeboxes. I read your profile. Never mind. Not important.

As far as 55-59 diff, you will have to do your homework. Widths are all online. Measure yours and see what comes close. 55-59 is pretty close. If I was switching over to open, I would try to go a little newer than that. 12 Bolts
are good and come in 3.73 which is the perfect ratio for acceleration and Hiway mix. Your truck width will be in the 60" range. Wheel Mounting Surface to WMS.

Also regarding what affect ratios have: there are "fill-in" calculation formulas and charts on line, to see various combinations for speed, mileage, acceleration, etc.

As in any proposed modification, you have to search the internet. Stovebolt is a good place to search and to ask those questions about what is involved/transmission/what fits what. Members who know what parts to get will advise. I think 52Carl has a very good grasp of this. Lots of "car" 5 lugs rears but not too many 6 on 5.5 lug patterns from a truck.

Not to over simplify but the basics are:
Make sure you know what components for your motor or your bell housing to use. Work your way back to diff. Buy the parts. That always helps to see the way forward. It gives you things to measure and contemplate. Sell the old diff and other parts to recoup funds.
Rip out the old and put in the new. In the rear, you are going from leaf to leaf. That's a matter of spring perches being welded on and tightening the U-bolts. Hook up brake line and Ebrake cable. The line is easy but the Ebrake may take some thinking. When rear end is installed and it's yoke is "aimed" correctly for pinion angle, and new or old tranny is mounted, measure and have a drive shaft made or modified.
It's planned out just like any other "home" project as I see you are aware.

I found This in our search function.

I have found that sometimes an automatic trans is very nice. Easier to install, no clutch, plenty of acceleration and overdrive. You do lose that manly tactile shifting feel however.

bartamos, yeah im into jukeboxes I have a 58 Wurlitzer 2204
I love the AMI continental looks like r2 d2, ever seen one?
you through me off abit I was thinkin truck parts hahaha wasnt even thinking about AMI jukes

I've seen the Continental in Photos only. Pretty neat. Yours is a nice one. Any visible 45 box is nice to have.

agreed

I'm hoping to do the same thing on my '53. I want to find a later truck rear end w/open DL and 3-speed to replace the existing 3-speed since it's only made for the enclosed DL.