pinion deph shims

M

mike cox

Junior Member
Hello,would like to know what shims are to be used to set the pinion deph on a, 1947, also where would one buy such shims. Thank you for your help. Mike
 
There are no shims available to set pinion depth other than pressing it all the way into the housing. With all the modern reproduction gear sets and bearing sets available, there is a possibility of machining error. There are shims for the differential side bearings available but other than different thickness of gaskets, that's about it.


There have been folks that have had troubles with pinion to ring interface but it's hard to tell through descriptions what the problem may be. Personally, I have to see it for myself before I can come to an accurate conclusion. The pinion being improperly located with respect to the ring gear, would give a gear mark of the pinion being too far in toward the centerline of the ring. It would extend off the toe of the gear. The pinion being to far out, would give a location to far outboard on the heal of the ring gear teeth. In other words, the mark would not center up on the tooth face of the ring gear or the pinion when performing a gear marking test.


Some of the new pinions are a bit too large on the pinion bearing journal that allows the bearing to slide on the shaft to get proper preload of the pinion bearing set. It's not supposed to be loose but the bearing should be able to slide on the shaft with a lower amount of pressure so the fit can not be an interference fit. If it is, then that can cause problems.
 
Like Rotorwrench said, there is no adjustment for pinion depth. Stick in there until it bottoms out. That shows you the accuracy of Ford's machining back then compared to the modern rear ends.
 
The mesh between the pinion and ring gear is set by the gaskets on each side of the banjo (center section). These gaskets are swapped in pairs from side to side until the proper mesh is determined by coating the pinion gear with a dye and then turning the assembly to transfer the pattern. This procedure usually requires several disassembling and reassembly, a time consuming process. The pinion does not contain shims, but must be properly seated in the banjo.
 
If you use a new ring and pinion ,and new timken bearings it WILL need a shim try .033 to get the contact corect. thats what I needed
Lawrie
 
Lawrie, You've got me all worried now...I just built a diff for a mate this weekend. I've never ever checked the pattern when setting up a banjo, used genuine Ford parts, and followed the prescribed method, never had any problems or noises.
When I built my Columbia, I used a new, aftermarket ring and pinion, and again, never checked the pattern. Just did it as per the Ford manual. I did have to polish the outer end of the pinion to allow the outer cone to be able to slide in order to achieve correct preload.
Obviously, it would've paid to check mesh pattern, but it seems fine to me; no noises, grumbles, broken teeth [so far!]
So now, you've got me worried that my Columbia is set up all wrong, and I need to do it again. And my mates one I just did last weekend, and every other diff I've built. Thanks mate!
 
Brian said:
Lawrie, You've got me all worried now...I just built a diff for a mate this weekend. I've never ever checked the pattern when setting up a banjo, used genuine Ford parts, and followed the prescribed method, never had any problems or noises.
When I built my Columbia, I used a new, aftermarket ring and pinion, and again, never checked the pattern. Just did it as per the Ford manual. I did have to polish the outer end of the pinion to allow the outer cone to be able to slide in order to achieve correct preload.
Obviously, it would've paid to check mesh pattern, but it seems fine to me; no noises, grumbles, broken teeth [so far!]
So now, you've got me worried that my Columbia is set up all wrong, and I need to do it again. And my mates one I just did last weekend, and every other diff I've built. Thanks mate!
Click to expand...

Proving once again, luck is better than skill ! 😁
 
I've never heard of any shims. What's the part number. You may need shims for the after market parts but not genuine Ford parts. Part number please.
 
I see the difference between the height of a set of genuine bearings marked ford and a new timken set is .010, so even if you use gen gears and timken bearings the pinion will be .010 further into the ring gear.
Lawrie
 
I've looked at my used sets and they're the Timkens made for Ford since they have the script on there. I read your previous post Lawrie and I can see what you are referring to. There are different manufacturers of R&P gear sets out there over time and they are not exact copies of OEM Ford. Your method of measuring pinion depth is as good as any for this design so I'll keep my old ones for that purpose. More modern axles generally have tools for this purpose but the Banjo, not so much.

Fabricating shims to fit against the pinion quill land and inner bearing would push the pinion further in toward the center line of the of the ring gear and a shim between the dual cup and the land down in the banjo housing would force the built up pinion assembly farther away from the center of the ring gear if necessary.

I'm curious as are others how you fabricate your shims since they would likely need to be custom made.

I've used the lathe to cut shims from a piece of pipe or shaft stock then surface grind them to fit the thickness and keep them concentric. Is this how you do it?
 
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Hi Guys,
For the sake of us shadetree mechanics.
So if you DONT check the pattern when installing a NEW ring and pinion and bearings ( timken), what will happen? Wont it just wear in a different place to the original .?
What is the worst case scenario please.
Dave h
 
Barnfind08,
Ford did not offer any shims so there is no such part #. I found some in a ford dealer in KY that were made for early fords. I have yet to have had the need to use any but I am holding onto them in case the need arises. I am curious as the last three sets of new gears I’ve used the pattern looked sufficient to me, it may have been .010” off but certainly not .030”.
 
35ragtop said:
Hi Guys,
For the sake of us shadetree mechanics.
So if you DONT check the pattern when installing a NEW ring and pinion and bearings ( timken), what will happen? Wont it just wear in a different place to the original .?
What is the worst case scenario please.
Dave h
Click to expand...

I spent 38 years working as a field service engineer for the manufacturer of gear manufacturing machinery & equipment in the USA, so I feel that I can confidently comment.

Gear sets are designed and manufactured to position the tooth contact so as to spread the load to the tooth evenly over the tooth for strength and to reduce gear noise. Mis-locating the contact will concentrate the load and cause premature wear and even tooth failure, as well as gear noise. short

In short, yes, if the contact is changed significantly, the tooth will wear, but not well and could cause catastrophic, premature failure.
 
the shims I used were from my box of shims,I think they were ones left over from a 9in gearset I did last.
But I will check and see
Lawrie
 
I have had to shim the pinion in about .030 when using new gears and bearings. They are available from Mcmaster carr as ARBOR SHIMS the quality of new parts especially bearings is sometimes questionable and tolerance stack up prevents proper gear mesh simply by adding or subtracting gaskets.
 
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