Trans fluid leak question
Thread Starter
Racer
Joined: Feb 2012
Posts: 442
Likes: 3
From: Hendersonville TN
Trans fluid leak question
1989 coupe. I've had an occasional trans fluid drip for a while now and finally got under the car after putting a new piece of cardboard down 3 days ago. I looked up from where the tiny drip hit the floor and saw a drop of trans fluid hanging off a flange on the front of the trans pan. I got a wrench to see if the pan bolts were tight and I was able to easily turn about 4-5 of the bolts about 1/2 to 3/4 of a turn. The rest were tight. At a recent visit to the shop for a new MC they told me I had a trans seal drip and that it wasn't bad enough to worry about. I'm thinking now that it was just a loose pan. Am I more on the right track than the shop? They also said my rear main had a small drip but not enough to worry about when I can clearly see the drain plug is missing the gasket and slowly drips over a period of time. Attached pic is where the trans pan meets the inspection cover (?). It was covered in grease from over the years and you can see the flange I'm talking about.
Last edited by HandsomeMike; Nov 6, 2013 at 03:24 PM.
Team Owner
Joined: Sep 2003
Posts: 25,375
Likes: 2,734
Wash everything down and dry it. Observe for a few days and see what develops. Secure all of the transmission pan bolts and at the "next" oil change deal with the drain plug gasket. I certainly wouldn't do anything out of the ordinary until you confirmed there were issues.
Thread Starter
Racer
Joined: Feb 2012
Posts: 442
Likes: 3
From: Hendersonville TN
That's the plan. I hand tightened each trans pan bolt without over tightening. Going to drive it this weekend and park it for a few days and see if it still dripping and from where. I wish I could find a trustworthy mechanic that didn't take guesses!
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
I have had problems with cork gaskets. They seem to become saturated with ATF and then it just oozes out right through the gasket.
I have had good luck with Farpak trans gaskets. They were recommended to me by Dana Wilkes of Pro-Built Automatics.
I have had good luck with Farpak trans gaskets. They were recommended to me by Dana Wilkes of Pro-Built Automatics.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
Wash everything down and dry it. Observe for a few days and see what develops. Secure all of the transmission pan bolts and at the "next" oil change deal with the drain plug gasket. I certainly wouldn't do anything out of the ordinary until you confirmed there were issues.
.. With the trans pan bolts retightened and the pan cleaned off you will know soon enough if its the pan leaking or a front trans seal...The same with the oil pan, once the oil plug gasket is put on you will have your answer...I never trust mechanics that I haven't known for a long while, they have to prove to me over time they know what they're doing ...
...WW
Thread Starter
Racer
Joined: Feb 2012
Posts: 442
Likes: 3
From: Hendersonville TN
The search continues for the mechanic. I've got one that I trust not to lie to me but I don't have faith in his diagnostics and I have another that I have been using as a primary who recently installed a new MC and had to bleed the brakes three times to get it right. They finally had to call another mechanic who told them that there is a sequence to follow. Once they did it right, the brake light went off and the new MC was working properly. And this is a big name franchise shop/tire company based out of Nashville, TN. (I don't want to say the company name directly).
Race Director
Joined: Apr 2003
Posts: 17,699
Likes: 1,667
From: moraga ca
Before you get that far, get a can of BrakeKleen and a few rags (and a pair of goggles) and spray all that crud off the bottom of the motor and tranny until you can see metal. Get it sparkling clean. Drive it around for a day or two, then crawl back underneath. You will be able to see if the leak is coming from the pan or seal or filler tube gasket or transmission coolant lines. Then you should plan your attack. Good luck.
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Thread Starter
Racer
Joined: Feb 2012
Posts: 442
Likes: 3
From: Hendersonville TN
After tightening bolts and a spirited drive it is now dripping a lot less and now is a tiny drip from each front corner of the pan. I really think it's the pan gasket. I'm going to tackle that job Saturday. Is it as easy as taking the bolts out and dropping the pan and then taking the screw out of the filter then replace in reverse order? I found a rubber gasket and filter kit at Advance Auto. Driveworks automatic transmission filter kit is the brand and description. Which brand and type of fluid do you all recommend? Doing the oil too so I can replace the drippy plug that is missing the gasket. Thanks folks.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
You have to be careful when removing the old trans filter, sometimes the gasket or O-ring that fits on the tube of the filter will get stuck up in the hole and you have to remove it with a small screw driver... The filter will just push up into place and seat, they can't go anywhere because the pan holds them in..I just go to Advance Auto and get their brand of Trans filter, most are mad in China so it really makes little difference...Make sure all surfaces are clean and dry before mounting the pan , take all the bolts up until they're snug and then take them up equal amounts working around the pan until there all to spec..I believe the torque setting for the bolts is (97 inch pds) but you may want to check the FSM to make sure..........WW
......WW
Last edited by WW7; Nov 12, 2013 at 08:25 PM.