34 rear differential rebuild information

R

RGC1

Senior Member
I am going to rebuild the rear differential in my 34 fordor and possibly a gear change, any good manuals or websites any body can suggest ?
I have done lots of diffs, just not any of this style or age .
Any help appreciated , thanks in advance.
 
I'll attach a couple document that might help you. One is for a Model A, but the information is applicable.

View attachment Differential-Rear-End-Restoration-Revised-2014.pdf

View attachment Rear axle assemply checks.pdf

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A decent little booklet from Vern Tardel that is worth buying is:

https://www.amazon.com/Ford-1932-48...Rebuilding/dp/B01JZXQ0LA?tag=atomicindus08-20
 
Here is a little "trick" that I do when working on these old beasts. You can make it easy to stand the housings up if you make a wooden box/frame to set the housing on. This is particularly useful when swapping gaskets and trying to get the preload, gear mesh and backlash setup.

I use a bare backing plate and bolt it to one end. Also, if you make the wooden setup tall enough, then there can be room for the axle to stick all the way through and not hit the floor (so consider that). Also, I made a steel plate to bolt to the banjo such that I could mount the whole assembly on my engine stand - that is a great help as well!

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Thanks that looks great I will do that looks like I may have to round up a few of the specialty tools also .
Thanks again
 
I'm in the same boat. I've rebuilt at least 100 rearends as a mechanic with the phone company, but I've never rebuilt an early Ford rear end. I have a pile of rearends sitting here. I have all the books mentioned. I have a NOS set of 3.54s waiting to go in a late '32 rear end but then I had a stroke and everything's on hold. I just don't feel like it???

Even though I haven't done one yet here's some advice. One of the main differences is setting up the gaskets to acquire the correct backlash and side bearing pre-load. It's just like a setting up a regular rear-end but you're using the axle housings gaskets to get the correct side bearing preload and "then" moving some or one of gaskets from one side or the other to get the correct backlash. The other thing is making sure you don't have pitted wheel bearings races which are "really common". They would need to be sleeved. I have the KRW pinion bearing pre-lube tool for setting the pinion preload. I see them for sale, but they are almost always missing the calibration spring, so they are useless. You could make up an adapter to fit the splines of the pinion gear and a small torque wrench to set the preload. Another tool unique to an Early Ford would be something to drive in the axle's seals. I still need to make up that tool or by a KRW one. You might want to buy a repro KRW tool catalog that shows pictures of all the Ford tools.
 
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Another thing I use to set the pinion preload.
I machined up a little pulley that is 2 inches in diameter, the mounts to the pinion shaft, this I wrap a length of cord around and use a good spring balance to pull on the cord,
It gives a really good pounds pull that is via the 2 inch pulley .inch pounds.
Lawrie
 
Thanks for the information that is great info and will help a lot , sorry to hear about your stroke hope all gets well for you in that area.
 
I bought a special torque wrench that measures inch/lbs - instead of the common ft/lbs. I made a little adapter for the pinion snout that allows me to use this torque wrench to set the preload. You also want a couple of those special wrenches for the pinion nuts.

I did my pinion removal in my hydraulic press - made a couple adapters from pieces of pipe to handle the various operations. The Vern Tardel book shows his methods of pinion removal . . . quite a few ways to skin the cat. I would try to find ORIGINAL vintage Ford/Timkin bearings for everything . . . I don't trust a lot of the modern stuff . . . but maybe that is just me. Best of luck!
 
Here are the wrenches mentioned above. 1 7/8 " X 9/32 thickness.I got these of EBAY yrs ago.
 

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Thanks guys for the info and the tool suggestion and where to get the book, that’s great that will help a lot. The plan is to change to 3.54 gear ratio when I rebuild anybody running that ratio with input ?.
Thx !!
 
I just had Strong's Garage change out the 4.10 gear set in my 34 roadster to 3.54 and wow what a difference its a totally different car to drive, at 60 the engine purrs along with much lower rpm.
 
Steve Staysko said:
I just had Strong's Garage change out the 4.10 gear set in my 34 roadster to 3.54 and wow what a difference its a totally different car to drive, at 60 the engine purrs along with much lower rpm.
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That’s awesome I talked to them just recently and they mentioned just finishing one, which would have been yours . I just seen them yesterday at the vintage swap meet, and was talking to them about it, also spent a few minutes talking to Harry , he went with 3.54 gears in there 1935 , said the same as you did. I would like to make some long trips , so that sounds perfect for want I am wanting to do.
 
Steve Staysko said:
I just had Strong's Garage change out the 4.10 gear set in my 34 roadster to 3.54 and wow what a difference its a totally different car to drive, at 60 the engine purrs along with much lower rpm.
Click to expand...


Would love to see your car looks very nice !!
 
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