Ok, that sheds a little more light on this mystery. It appears Allison has re specced this part 2 if not 3 times.
A question I had in the other discussion was that the part number for the old bearing in the service information letter(SIL 17-WT-11en) that Langstonhs referenced, was not the same as that listed in the 24P. That pic of service information letter 29-WT-96 you posted above on the left references the old part number in the 24P for the roller thrust bearing. Its hard to read but if I read it correctly, they updated the part but kept the same (original?) P/N23015799
This also agrees with the tech manual(ch21) saying all before the S/N listed in that SIL need to be replaced during any major trans service. I put a screenshot of that manual page in the other discussion.
So here is how I read this:
1. In 1996, at S/N 6510072174, they updated P/N 23015799 with an improved roller thrust bearing But kept the same P/N. SIL 29-WT-96 directs all previous s/n transmissions to be retrofitted and further troubleshot if debris Is found at the drain (This was the first change).
2. Somewhere between 1996 and 2011, that original roller thrust part number 23015799 changed to roller thrust bearing P/N 29544806. Was it re-specified again? Is there another SIL-??-WT-?? Floating around specifying another serial number change/update point? It could also be that it changed when they introduced the 3700SP, the mostly similar follow-on to the MD3070PT...
3. In 2011, at S/N 6511014364, they released SIL 17-WT-11en, directing roller thrust P/N 29544806 was discontinued and it was to be replaced with composite thrust washer P/N 29545936.
What I get from this is that if you have a MD3070PT transmission prior to S/N 6511014364, your roller thrust bearing can be retrofitted with the composite thrust washer, as it appears that every type roller thrust they have tried in that location has had higher than expected failure rates...
I have a question into an Allison rep to clarify this, and will let you know what I find...
