A Slight Grind

[Shark Pilot]

I have a 1982 DMC with 17,000 on the clock. The transmission shifts smooth and reverse is butter. However, when I'm really getting on the gas and driving it like a sports car, sometimes between shifts I get a slight grind. Most notably between 4th and 5th. The car will go into gear, but there is an audible grind and I can feel it in the stick. This is not always, and it only happens when I'm getting on it hard and shifting QUICKLY. If I shift normally it NEVER happens. Ideas?

[DMCMW Dave]

I have a 1982 DMC with 17,000 on the clock. The transmission shifts smooth and reverse is butter. However, when I'm really getting on the gas and driving it like a sports car, sometimes between shifts I get a slight grind. Most notably between 4th and 5th. The car will go into gear, but there is an audible grind and I can feel it in the stick. This is not always, and it only happens when I'm getting on it hard and shifting QUICKLY. If I shift normally it NEVER happens. Ideas?

How old is the gear oil and/or what kind is in there?

[Mario]

Synchros can't get everything up to speed fast enough, possibly? This will be affected by the thickness of the oil you have.

[David T]

How old is the gear oil and/or what kind is in there?

And how much is actually inside? If you don't know when the oil was last changed or what kind is in there you need to remove it and put in fresh stuff. That should fix it and if it doesn't the next step is to check the linkage to make sure it moves smoothly, is properly adjusted, and there are no worn parts (the rubber bushings) in it. Be sure to remove the level plug on the side FIRST before removing the drain plug.

[Shark Pilot]

How old is the gear oil and/or what kind is in there?

Actually I have NO IDEA. I suppose this is a bad thing. Any idea on what kind I should put in there and how much? I've owned the car for 6 years, but never changed the tranny oil. I should mention that 4 of those years it was in renovation so I've really only operated it for about 2 years.

Transmission was rebuilt at Bauerle Auto and the 2nd gear roll pin was replaced. Syncros not keeping up could be a problem because it only happens when I quick shift. However I have no idea how to fix that either.

[Shark Pilot]

And how much is actually inside? If you don't know when the oil was last changed or what kind is in there you need to remove it and put in fresh stuff. That should fix it and if it doesn't the next step is to check the linkage to make sure it moves smoothly, is properly adjusted, and there are no worn parts (the rubber bushings) in it. Be sure to remove the level plug on the side FIRST before removing the drain plug.

Ok I'm just gonna change it based on not knowing WHEN it was last changed anyway. Besides I know it hasn't been touched in at least 5 years and it's been sitting a lot so I might as well eliminate that variable. Thanks!

[David T]

Ok I'm just gonna change it based on not knowing WHEN it was last changed anyway. Besides I know it hasn't been touched in at least 5 years and it's been sitting a lot so I might as well eliminate that variable. Thanks!

The stuff to use is Castrol HYPOY C SAE 80W-90 gear oil. Takes just under 4 quarts. The oil doesn't wear out and 5 years is not that long. What does happen is there is a VERY slow drip but over a bunch of years enough can leak out to cause shifting problems. Drive the car enough to warm up the oil before draining it out. If you haven't flushed the clutch and brake hydraulics in the past 2 years, that should also be done.

[Jonathan]

The usual advice is to ensure you can get the fill plug out before going ahead and removing the drain plug. Drain plug is right on the bottom, pretty much middle middle; and the fill plug is on the driver's side, just in front of the axle.

[Morpheus]

^ Actually, the fill plug is on the passenger side of the tranny. I just did mine a couple of days ago. 8)

[Nicholas R]

I would also say do yourself a favor and buy one of these. It is a 10mm square female socket. Makes draining and filling a breeze. It adapts perfectly to the square drain plug. An open ended wrench will often round out the plug, or break the wrench if it's really stuck; and a vice grip just tears it up. I have one of these and it works perfectly.

for $7 and free shipping you cannot beat it.

http://www.amazon.com/CTA-2048-10-Millimeter-Female-Square/dp/B008TOHA6Q/ref=sr_1_16?ie=UTF8&qid=1441079359&sr=8-16&keywords=10mm+square+socket&refinements=p_85%3A2470955011

36406

[Shark Pilot]

I would also say do yourself a favor and buy one of these. It is a 10mm square female socket. Makes draining and filling a breeze. It adapts perfectly to the square drain plug. An open ended wrench will often round out the plug, or break the wrench if it's really stuck; and a vice grip just tears it up. I have one of these and it works perfectly.

for $7 and free shipping you cannot beat it.

http://www.amazon.com/CTA-2048-10-Millimeter-Female-Square/dp/B008TOHA6Q/ref=sr_1_16?ie=UTF8&qid=1441079359&sr=8-16&keywords=10mm+square+socket&refinements=p_85%3A2470955011

36406

Thanks guys! I ordered that tool. I'll get on it this weekend. I appreciate the data. I DO have a VERY small transmission leak, about 2 drips per 2 weeks, but I'm not sure if it's the rear engine main seal or something else. Hoping it's not the main seal. That's a PITA on any car.