transmission stuck in gear

[billy]

[T. Highway]

That does not look good. It looks like further disassembly will be required for cleanup, inspection, bearing replacement and to get it sealed up properly.

Bert

[billy]

these old trannys are suprisingly robust.
my old t98 had something similar and i flushed it out and drove it
ten years and many hog hunts later its still going fine

[M60TC]

I agree with Bert, you should further inspect the transmission. We used to flush the transmission with Diesel fuel then drain and refill with new GO-90 Lub but we knew the History and Maintenance of the Truck.

Don

[billy]

i am not pulling that transmission unless i have to
with the price of labor these days
its a tossup to simply buy a rebuilt one from someone like novac
or pay to have someone spend hours on it.
the price of14 hours of labor will buy me one with a guarantee .
if it breaks
i will rebuild/replace it
spinal arthritis keeps me from doing this stuff myself like it did way back when

[CSCameron]

Flush it, fill it, run it. They are tough.

[MSeriesRebuild]

WOW!! All the bad advice offered as in "flush it and run it" is just not good, hoping you are much to smart to pay attention to it. Obviously there will be rust damage on gear teeth and bearings, especially the ones that sit submerged in all that water blended oil for any period of time. It will likely be very noisy, and rust damaged gears and bearings will wear at a very accelerated rate. Bottom line, if you follow that strategy, and the trucks logs many miles at all, especially at highway speeds; most likely issue in your near future is a complete and utter major failure that will likely destroy the whole gear box in the process. It is doubtful you would even have an acceptable core left to turn in for that rebuilt gear box; but based on what you have described, you wouldn't have an acceptable core now if they looked inside before accepting it. I will say this; you may or may not choose to follow sensible advice, and that is certainly your call. I for one will not offer advice that is certain to cause you problems and cost you big $$ in the end; and I hate seeing here that there are those who are willing to do just that.

[billy]

do all of these transmissions and transfer cases grenade when they get condensation/water in them?
i know that my willys jeep had milkshake in both axles, the tranny and the transfer case
i replaced the leaky seals and the fluids a few times until the oil stayed clean
and drove it everyday with no issues

[Elwood]

do all of these transmissions and transfer cases grenade when they get condensation/water in them?
i know that my willys jeep had milkshake in both axles, the tranny and the transfer case
i replaced the leaky seals and the fluids a few times until the oil stayed clean
and drove it everyday with no issues

The question isn't if it will be damaged or fail, but how long before it will be damaged and eventually fail.

When I bought my M37, I checked the transmission lubricant level and all seemed well. So I drove it for a summer. When I finally started disassembling it, and drained the trans, I discovered that it had water in the lube. Did it explode on me and leave me stranded? No. Were the bearings and gears in pristine condition? No, and had I continued to drive it that way, it would have eventually started making noise (or should I say more noise) and someday a bearing would have failed.

Corrosion is the enemy of machined surfaces and tolerances, and water in the lube will eventually lead to corrosion. No way around that.

Keep in mind that Charles is a professional in what is a hobby for the rest of us, and he should (and does) work to a rather high standard. What each of us decides is acceptable for our trucks is a different question than what he can or should recommend, especially on a public forum.

[MSeriesRebuild]

Here is the typical outcome; realize that the hardened surface on gears / bearings, etc., are only a few thousandths deep. When water is allowed to sit in a unit, it separates from the oil and sits on the bottom of the case. Any gear teeth, bearings, or whatever that are turned so they are submerged in the water for any period of time will rust aggressively; destroying the hard surfaced area. If the unit is put back into service, the oil and water mixes making the milky mess that you found. By this time the damage is done, so changing the oil and putting in new will not reverse the damage that is already in process. The rusted areas will wear very rapidly because the hardened surface is destroyed, it is now soft metal taking the beating from heat and rubbing action, these parts are ruined. As time goes on, dissimilar wear surfaces become more and more out of sink; this makes for a noisy gear box, that only gets worse as the accelerated wear progresses. If you push it long enough, a massive failure will result and the metal particles from the parts breaking down and circulating in the oil over time will absolutely destroy the whole gear box.

OK, some say they are running boxes that were watered down without issue. Well here are the facts on that; if the water stayed there long enough to start even a minor rusting process, pits on gear teeth and bearings started to form quickly. Even minor pits on these critical areas will cause a noisy box from the get go, and you can count on that getting nothing but worse causing an eventual failure. Another fact, you can not tell how bad the situation is except you pull the box down, clean, and inspect components closely; and NO this doesn't mean flip the top off for a quick look, put in new oil and assume all is wonderful. You can't see very much of actual damage that exist until you disassemble and clean. You may open it up and be one of the lucky few who does not find significant issues. In this event, you can clean and reassemble replacing any necessary components and possibly get a decent run life out of the unit. If you don't follow common sense advice now, even if there isn't much going on at present, you will still end up with a mess; rust does not stop, damage does not heal itself. No matter how minor it is now, whatever rust is there will continue to grow and do damage even if the water is removed.

This should give you a pretty good explanation of your options, in my mind it's a no brainer. You can proceed however you see fit.

[RMS]

2x what Charles said........and really it may seem like a daunting task to tear it down but it is an easy job.

I spent months fretting about the job of rebuilding my t18 (oops my bad) T98 (canadian m37)after finding chunks of needle bearings in the oil. I went around to shops and got heart stopping quotes. in the end it took me 4 hours and $32.50 for washers and needle bearings to rebuild the transmission. I was lucky that there was no corrosion and all the needles were accounted for. (must have been contaminated oil). in the end removing the doghouse was a bigger job than tearing into, inspecting and rebuilding the transmission....

...also many transmissions and tcases in our beloved m37s are on or have been run with heavy 90w gear oil that dose not allow for proper lubrication. such units should be disassembled cleaned and inspected.

[billy]

ok
you guys talked/scared some sense into me
i am in the middle of shopping around for master rebuild kits for both the NP435 and the NP200
once they are opened up and REALLY scrutinized.
i will know what condition the innards are in and what needs to be replaced
i am almost certain i will want ready sleeves* for everything that will accept one.
where do you folks suggest as the best place for these kits?
thanks again!

*or whatever they are called

[billy]

one more thing
the govt manual i have specifies 90 GO oil
what else is supposed to be used?
since thats what my papers say is called for
thats what i have been using

[RMS]

the mighty 5 page transmission oil thread http://www.g741.org/PHPBB/viewtopic.php ... ission+oil

should be a sticky or in a new thread and we could call it......: things every m37 owner should know that the manual doesn't tell you

[Jess]

ok
you guys talked/scared some sense into me
i am in the middle of shopping around for master rebuild kits for both the NP435 and the NP200
once they are opened up and REALLY scrutinized.
i will know what condition the innards are in and what needs to be replaced
i am almost certain i will want ready sleeves* for everything that will accept one.
where do you folks suggest as the best place for these kits?
thanks again!

*or whatever they are called

DC Trucks has parts for the NP200 and maybe the trans on Ebay, or you can contact him directly. He is located in Oregon and has been knowledgeable and fair to deal with.