Transmission Oil Change Question

[Don Cavey]

Happy New Year everyone. Hope we all have a very healthy and productive year.

You may have read that I changed the oil in all gear boxes, differentials and engine this week on my truck. All was well except for the transmission. I knew from checking, the oil in the transmission was milky, actually looked like coffee with a lot of cream. Certainly, before I owned it, rain water was seeping into the transmission around the shifter.

I changed that oil and intend to change it again in a few weeks. My question is, "Should I remove the PTO at the same time, drain it to make sure I get the water out?

I am not having any problem with the transmission. Hopefully, there was no damage to any bearings. Since I have owned the truck, the operation of the transmission has not changed. I did find one small tooth chip, but the drain plug only had "Normal" amounts of filings.

Thanks for all of the help and guidance since I have owned this truck. It is nice to re-familiarize myself with the M715. It was a long, long time since I drove one.

[brute4c]

If it were me, I would...that way I could clean it better and inspect more...plus you make sure you get out all you can get out of the nasty gunk.

[Blitz]

I agree...
I would for sure pull it.

On the NP 202, the Pto sits above the bottom of the Transfer case, so it has its own oil pump, gear driven, inside the pto to assure complete oiling.

The T-98 PTO may be similar.... Sitting above the bottom of the tranny case, but "holding" a reserve of oil in the housing.

For sure You have gunky gear oil stuck in the recesses of the PTO.

Be exceedingly careful of the tolerances for the backlash though, as I "believe" those are set with the gasket thickness, and should be .020 ... but dont quote me on that, just be aware before dis assembly.

Still worth it.

I might even personally use some brake cleaner, and a drain pan to douse it good.

[67smith]

I would pull as well, but as stated be careful of backlash, I believe you have to pull shifter cover to set backlash, which is indeed set with gaskets.

water rises with heat, so it condensates, before setting back to the bottom on oil, this leads me to believe that water would collected in the little used PTO and just sit, rather then mix back with the tranny

[Don Cavey]

Today, I went for a 35 mile trip around the area. The one thing that I immediately noticed was that the transmission shifted easier. As the trip progressed, the transmission made no "protest" noises when downshifting. It easily went from gear to gear and did it quietly. Needless to say, I am a very happy camper. I just need to keep moving on, one item at a time. I intend to "visit" every component and assure myself that it is safe and reliable.

Thanks for the suggestions. I will change that transmission oil one more time later this year.

[kyken]

Great to hear of your successful drive Don!! Sounds like a good one!!