1936 ford diff gear change
 

Hi Guys,I'm planning a ring and pinion change in a 36 ford and wondering about any special tools I may need, Thanks

Re: 1936 ford diff gear change
 

did that not too long ago. what gears are you going to use? remember the splines on the drive shaft and the pinion are different requiring an adapter. we bored out and installed a drive shaft coupling into the original hollow 36 drive shaft. since we still have the 21 stud engine we went from 4:11 to 3:78--we talked about a 3:54 but decided against it because we have hills and the owner really did not want to go that fast anyway!

Re: 1936 ford diff gear change
 

As mentioned in post #2 the pinion if the rear is the original 36 more than likely will be 10 spline any new ring and pinion sets are only available with six splines. The 36 drive shaft is a tube type the female pinion end coupling is welded to this tube so theres a problem when changing the gears to deal with when it comes to the pinion spline count.
Ronnireoadster

Re: 1936 ford diff gear change
 

Special tools; hub puller, and a spring spreader would be handy too. Tools to remove and replace the oil seals inside axle housings. A press for removing old pinion assembly from banjo

Re: 1936 ford diff gear change
 

A spring balance and little pulley that is 2 inches in diameter to set the pinion preload.
Lawrie

Re: 1936 ford diff gear change
 

Now that's getting technical Lawrie; I hold pinion shaft in a vice and spin the banjo as hard and fast as I can. Should only spin about 3/4 turn. OK, shoot me down....I learnt that system here on the 'barn somewhere....All I know is that it works.

Re: 1936 ford diff gear change
 

For the pinion pre-load a pointer style torque wrench that reads in inches
The pinion nut are 1 7/8" They have to be tightened and loosened. There are two thin nuts back to back with only a thin lock plate in the middle.
A dial indicator for 0.001" with magnetic base.

Re: 1936 ford diff gear change
 

dxxm engineers! I am an somewhat old millwright and just use feel to set the pinion preload. If you are going to use 3:78 gears then locate and good rear axle with those gears and swap out the whole banjo and then bore the drive shaft and press in spline adapter and go for a ride. cheaper and easier in the long run

Re: 1936 ford diff gear change
 

29, Where do you live in Hellinois? Send me a PM if ya don't mind.

Re: 1936 ford diff gear change
 

What gear ratio are you trying to get too? I just installed a set of 3.54's in my late 32 style axle - was a bit of work, but nothing too bad as long as you're used to mechanical work, have a hydraulic press, know how to set preload and backlash, etc.. If you're NEW to all of this, then I'd recommend finding somebody who knows the ropes . . . maybe team up with them.

Re: 1936 ford diff gear change
 

I'm thinking the other guys have covered everything necessary on special tools, but would just like to mention that I rebuilt the rear in my '35 fordor sedan last summer using 3.54 gears with 6 spline pinion. I used the original '35/'36 tubular type driveshaft, and bored the ID of the 10 splined bung on pinion end to provide a press fit with a stock 6 to 6 spline coupling. We milled two openings thru to the ID, 180° apart, on the 10 splined bung, about 1/4" back from the original weld holding the bung to shaft tube, prior to pressing the 6 to 6 spline coupling in place. After the coupling was pressed in place, we welded the 6 to 6 spline couplings in place thru those two milled slots, while keeping the pin holes in the coupling and bung aligned. This locks the 6 spline coupling in place and prevents damaging/distorting at the begining of the splines if attempting to weld there.
We rebuilt the transmission using the later, '39 - '48 improved syncro gears with a 29 tooth cluster gear and an input shaft with a 15 tooth gear. This combination of trans and rear gears gives very smooth acceleration off the line in first gear, without the need to slip the clutch to get moving.
I'm also running a '35 21 stud engine, with poured babbitt mains, 0.030" over bore, and milled cast iron heads. I have no problems crossing over the mountains of Maryland, West Virginia, and Pennsylvania in high/3rd gear. With this combination, I like the 3.54 rear gears, much better than the 3.78 gears that were previously used in this car.

Re: 1936 ford diff gear change
 

John, I've done a couple of these now, much the same as you, however, I tig weld around the seam, evident in your last photo, also drill and countersink several holes around the periphery of the original outer 'casing' and mig through them into the new 6 spline sleeve to achieve good penetration.

Setting up the driveshaft in the lathe to bore out the rear, ensures the whole assembly runs true. All in all, in my opinion, this setup is superior to the solid driveshaft setup with the centre support bearing as introduced in 37.

Re: 1936 ford diff gear change
 

Sounds good Brian. I agree, doing the tubular driveshaft as the pictures show, is easier and more cost effective than going.with the solid drive shaft and center bearing. I didn't think this was true at one point in time, but after doing my last rear rebuild this way, I am now a believer. I can have a tube drive shaft done for 6 spline for about the same cost as a new center bearing.

Re: 1936 ford diff gear change
 

John,
Did u have the drive shaft checked and adjusted for true after having the 6 spline coupler installed?

Re: 1936 ford diff gear change
 

All of this, but with respect, a KRW type hub puller, never a three finger type.

Re: 1936 ford diff gear change
 

Yes Rob, the machinest who actually modified this driveshaft to my specs, specializes in making custom driveshafts/drivelines and the repair of most any type of driveshaft. During the process he checks for TIR, ID to OD concentricity, and balance, making any corrections as necessary.

Re: 1936 ford diff gear change
 

Great catch Allen, and with respect, sorry about posting all the other trivia.