I need to replace the pinion shaft bearings on my D2 5U7066, these bearings are located at the rear of the shaft just ahead of the pinion gear. My parts manual only lists a single ball bearing that is held in place by a retaining nut. My pinion shaft has two tapered roller bearings placed back to back that are held in the retainer by a thrust plate. It doesn't look as if it has been modified from the ball bearing setup. I was wondering if anyone has part numbers for these bearings and races that I could take to Cat. No one I've contacted so far has been able to get them.

Appears you have the 5H6053 bearing group - (field changeover)
My parts manual shows it applicable to 5U13237 to 5U14773 but probably can be accommodated on earlier models. Also uses the later 4H7698 pinion shaft.
Uses two tapered roller bearings on one outer race part # 4H7791-bearing assem.

These parts became standard production at sr. # 5U14774

Could not find it in my bearing interchange list. Check actual parts for numbers that might make interchange.

Try 4h7701

Thanks Josh,
The "9" is actually a "0".....to much fine print:o
Still couldn't find the interchange for 4H7701 but there is a better chance of the required number actually on the parts.

An interesting note on these double taper roller bearing sets, they are not just a group of two taper roller bearings and a shell that can be purchased seperately and put together, but are ground to final tolerances as a group at the factory. You will often find the part number for the assembly hand scribed on the outside of the shell.

Josh

Thanks for the information, there are numbers scribed on the bearings. I figured it was a revised design over the single bearing setup. Is there a preload spec for this bearing unit, similar to that of a pinion shaft in a conventional differential, or do you need to buy a new bearing group, already setup?

I think a new bearing group is the only way to do it, there is no provision for a preload setup, try Emerson Bearing, I have had good luck with them.
www.emersonbearing.com/

Hi Team,
these Bearing Assemblies are code numbered because they have been factory set up for correct preload/clearance. The components are marked with a Code/Serial No and must not be mixed with other bearings or the factory setup is lost, also you will note that one cup and one cone is marked with the code No's plus an "A" or a "1" or similar and must be kept paired together for the same reason, also any spacers with the Code are part of the Assem. and the same applies.
Hope this helps,
Cheers,
Eddie B.