FM 146 with stuck fill plug

[mk42gunner]

Went to change the gear oil in my 88 and the fill plug on the FM146 is stuck, not just a little tight either. The previous owner swapped the manual into the truck from an auto.

The fill plug looks like it has had a pipe wrench on it before, it is all chewed up and rounded. Sockets just spin.

The pan looks like it may be leaking, but the oil could be coming from the rear main seal, I didn't really check that.

Can the FM 146 be filled by removing the shifter like an M5OD? I really need to get some oil into it, the shifter starts to bind after driving about twenty miles at highway speeds.

The one smart thing I did was check the fill plug before draining the tranny....

Thanks for the advice,

Robert

 

[Thrashingrage]

Sounds like me and you have similar problems. My plug is in about the same shape on my FM-146, some deadbeat rounded it pretty bad. I managed to get a pair of vice-grips on it and it came loose. I'd put some Liquid Wrench or the like on yours before trying to get it off. My tranny was supposedly rebuilt by a previous owner some ten-odd years ago, so who knows what kind of job they did in terms of seals, bearings, etc. To give you an idea, they used RTV instead of a seal on the pan - it was leaking a very small amount. I just pulled it off today and got a rather nasty surprise in that someone put ATF in the thing. My plan is to get as much of the fluid out as possible and then put some gear oil in there and drive it for a few hours. Once it's all nice and warm, I'll drain it again, replace the pan gasket, and fill 'er up with some decent gear oil. As far as the rear main seal goes, I am almost positive that mine is leaking as well, as I get some oil out of the drain hole in the bell housing. I also noticed a little leak from between the bell housing and the transmission case itself. I'm not sure if that's another rear main seal symptom or not, just hoping that it's not my front input seal or another gasket (or lack thereof). Anywho, I'll try to keep my eyes and ears open for a replacement fill plug, believe that it's an m15 or a 5/8ths. I tried O'Reilly and Ebay for one but no luck. I'll let you know if I find a source for 'em short of pulling one off of a wreck.
Cheers,
Josh

 

[alwaysFlOoReD]

I'm not sure about filling thru the top but why not.
I've removed rounded bolts and nuts with a cold chisel. Make sure to go in the right direction, tho sometimes making it tighter a bit first does help. Get the cold chisel started with hammering an indention into the side of the nut and then angle the chisel to about 75 degrees, and start hammering. It takes a while but eventually will come out.
Good luck,

Richard

 

[mk42gunner]

Well it had some kind of oil in it; not sure if it was all gear oil or not, it seemed pretty thin. There also wasn't more than two quarts total....

The drain plug came out with no problem, the fill plug is still stuck tight. I pulled the pan, the bolts varied from just past snug to about 50 lb-ft of torque. I cleaned all mating surfaces and cut a new gasket.

Removing the shifter did allow filling from the top, the nylon shift balls or bushings looked good.

As for the fill plug; I thought about welding a short section of 1/2" rod to it and using my stud remover, but decided against it. I really don't want to put that kind of heat close to aluminum threads.

We used to use cold chisels to remove bolts and screws from motorcycles, I had forgotten about that, but it does work.

I think I am going to look araound for a M5OD. If I can buy one when I don't desparately need one, I may be able to save some bucks. I am kind of keeping my eyes open for a wrecked 4x4 with a 4 liter that I can rob all the parts from, instead of buying everything individually from various junkyards.

Thanks for the opinions guys, I appreciate it.

Robert

 

[adsm08]

I prefer to fill through the shifter. It's easier and cleaner if you don't spill all over the carpet.