Changing Gear Oil

Camp · Post by **Camp** » Tue Mar 16, 2010 5:20 am

Hello,

I am new to this site. Just got a 1952 M37 been parked uncovered in Alabama for 10 years. Lot of rust. I was planning on changing the engine oil and gear oil. I drained the gear oil, but now can't figure out how to refill it. Also, the engine oil plug has been replaced with some sort of intent star plug, about as big around as my pointing finger. How do I replace the gear oil in the transfer, and what type of equipment do I need to do this. Thanks for any suggestions, I will try to get some photos.

Post by **Cal_Gary** » Tue Mar 16, 2010 5:29 am

Welcome aboard, Camp! This is THE site for your M37 issues-post any time you like!

There should be a 1/2 drive fill plug on the left side of each diff, just above the center line. Squirt your GL90 in there until you can feel it on your finger-do not overfill it.

The transfer case also has a 1/2 drive fill plug on the driver's side, again just above center-GL90 goes there too. Same for the tranny-a;; gear boxes have drain plugs on the bottom.

Your oil pan plug is actually the correct plug-most folks here use a 1/2 drive extension into the center of the plug to take it out.

Don't forget your steering box-it has a fill plug on top-GL90 again goes in there.

Again, welcome to the forum!
Gary

Nickathome · Post by **Nickathome** » Tue Mar 16, 2010 8:29 am

I don't think you can over fill the diff's. Just fill until the gear oil barely starts to ooze out, then reinstall the plug. Thats what I do.

refit1701 · Post by **refit1701** » Tue Mar 16, 2010 8:34 am

Welcome, Camp!!

Where about's in Bama are you? I live in the Birmingham area and we have a MV club:

http://www.ddmvpa.org/

Several of us have M37's. We are having a meet at the Battleship Alabama in Mobile April 9th and 10th. We'd love to have you drop by if you can.

Our club covers all of Alabama and parts of Florida.

cuz · Post by **cuz** » Tue Mar 16, 2010 9:04 am

Camp,

Welcome to the group. You should get your hands on copies of the service and parts manuals. TM 9-8030 has a complete lubrication section in it and well illustrated. Click on the "Tech Manuals" link at the upper right of this page.

Camp · Post by **Camp** » Tue Mar 16, 2010 10:38 am

Thanks for the great input. The oil pan plug is a receased / indented plug that appears to be a star, that I can stick my index finger into. Does this make sense?

I live in Birmingham as well, but the truck is in Walker County. We put two new batteries in it and got it to turn over, but it hasn't cranked yet. I had to put a new fuel pump on it. I have replaced the oil filter and am currently working on the oil issues. I plan to take out the spark plugs and spray some Marvel Mystery Oil into the spark plug holes. I also plan on draining the gas tank and putting in new / fresh gas. Any other suggestions?

refit1701 · Post by **refit1701** » Tue Mar 16, 2010 11:34 am

If you are thinking of driving it home....

Brakes, Brakes, Brakes!!

Nearly the first thing anyone does with any old MV is the brakes.

Camp · Post by **Camp** » Tue Mar 16, 2010 11:51 am

That's a very good point. The reason it was parked ten year ago was because the brakes went out, and the previous owner never got around to fixing them. Expensive? Can a beginner handle a brake replacement project?

Post by **Cal_Gary** » Tue Mar 16, 2010 12:31 pm

Brake job can be easy or difficult, depending on your degree of repair.

If you are going full-bore, replacing the master cylinder, wheel cylinders, linings, and lines, yes, it's pretty basic, but that brake shoe retaining spring is a bear....

However, if you are only doing enough to get brakes at all, this can be difficult because some wheel cylinders may be frozen, or so worn out that fluid may bleed past the cups. Also watch out for hacker work such as using copper tubing instead of metal-copper will rot away and fail when you need the brakes the most. The linings may be worn out as well, but fortunately there are a number of reputable vendors that have parts available.

Cuz mentioned the 9-8030 manual-a must for properly adjusting your brakes, along with a treasure-trove of other great info.
Gary

refit1701 · Post by **refit1701** » Tue Mar 16, 2010 2:03 pm

Brakes aren't difficult if you are used to turning wrenches.

I'd inspect the inside surface of each wheel back plate and see if there is any obvious leakage. Inspect the brake lines for damage or leaks.

Of course, finding out what the previous owner means by "went out" would help. No pedal? No stop? etc.

Glenn · Post by **Glenn** » Tue Mar 16, 2010 3:14 pm

Your oil plug sounds right, as mentioned a 1/2 " drive ratchet or breaker bar works in there. You're really taking a chance if you don't do a 100% brake job, especially if you lack experience in knowing what's good or bad as far as parts go.

SierraM37 · Post by **SierraM37** » Tue Mar 16, 2010 8:31 pm

You've got a great support group here to help out. You might consider having it towed home. Getting it going add's to the danger if it doesn't stop! That's almost 7,000 lbs. of good ole American Steel - Twice the weight of most cars on the road and you'll blow right through them if you can't stop and they are! Your bumper is higher than most others as well so you'd be mid trunk or worse at impact. Best hundred or so dollars you could spend to have peace of mind.

cuz · Post by **cuz** » Tue Mar 16, 2010 8:52 pm

I would assume you are not very familiar with many items on the truck. The star type drain plug is an example. An experieced mechanic would know immediately what fits in it. You haven't given us any indication of your experience and skill level in heavier truck repair. For the un-initiated the brakes will be a very big challenge. Sitting that long you have several major tasks between you and a useable set of brakes along with the need for some serious tooling. There's jacking the old girl, jack stands to obtain, breaking loose some serious size lug nits and most likely you will not have the correct lug wrench and probably do not have a 3/4" or 1" drive air impact gun. Once off the ground and wheel off (read serious heavy wheel and tire) you then must disturb gaskets, seals and bearing locking nuts to get the drums off. Then there is the issue of brake spring tools, hones if trying to save old wheel cylinders and the list will keep growing. There's the need for the correct axle nut socket wrench as well. This is a tough enough job in the shop. Out in the field you are really stacking the deck against yourself. As I mentioned above the manuals are a life saver.

Nickathome · Post by **Nickathome** » Wed Mar 17, 2010 2:37 am

Just some advise if you are going to work on the brakes. Save yourself some real headaches and if need be simply replace the wheel cylinders. When I did mine, I took a look at the old rusty ass ones I yanked off. I personally can't understand the logic of trying to resurrect some old rusty POS wheel cylinder. New Wheel cylinders don't cost all that much. Better to replace IMO this way you know you have brand new ones that should last a while.

Don't be scared off by a brake job though. I thought it would be a real bear but once I dove into them, it became one of the easier projects I worked on.

Lifer · Post by **Lifer** » Wed Mar 17, 2010 2:41 am

Everything you say is true, Cuz. I just hope you hven't scared the poor guy to death. That he's not an experienced mechanic was evident with his first question. This truck will soon turn him into one, but he'll need our help along the way.

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