Psssst! Tell me your secret ...
07-20-2017, 05:18 PM
#2
Le Mans Master
Make double sure the pan is flat and use a Dura-prene gasket. That's the black color gasket that looks like rubber, but it's actually impregnated cork. And don't overtorque.
07-20-2017, 08:36 PM
#3
Melting Slicks
i usually go around skipping every other bolt, then go back and skip the ones i did before.
tighten in stages and let sit for awhile (10-15min) between tightens.
i do the same for sump pans as well.
and while the pan is off put a drain plug in it.
tighten in stages and let sit for awhile (10-15min) between tightens.
i do the same for sump pans as well.
and while the pan is off put a drain plug in it.
Last edited by riverracer au; 07-20-2017 at 08:39 PM.
07-21-2017, 01:21 PM
#6
is it a factory pan or aftermarket?
did you check it on a flat surface to make sure it isnt warped and none of the bolt holes are distorted?
did you check it on a flat surface to make sure it isnt warped and none of the bolt holes are distorted?
07-21-2017, 01:31 PM
#7
Team Owner
Pound any dimpled bolt holes on the pan rail FLAT; clean the oil pan rail and mating trans housing surfaces clean of ANY oil/dirt (lacquer thinner works well); use a FelPro composition (cork/rubber) gasket; put a light wipe of Permatex gasket sealer on the oil pan side of the gasket; install bolts loosely, then torque to 1/3 of rated torque; let pan sit overnight to let the Permatex set up; torque bolts to 2/3 of rated torque; make final torque pass to full torque. DO NOT OVERTORQUE THE PAN BOLTS.
07-21-2017, 05:46 PM
#8
Team Owner
As well as making sure the pan is flat, as suggested above, make sure all of the retaining bolt holes are CLEAN, and free from residual tranny fluid. Torque the bolts to 8-9 ft/lbs, starting from the middle and working outward.
07-21-2017, 06:03 PM
#9
Team Owner
A good friend of mine worked at a Cadillac/Buick dealership and he was their automatic transmission guru and he said that 99% of leaks occur from the pan sealing surface not being flat and dimpled bolt holes from over torque. He always pounded the sealing surface and bolt holes flat even if it looked OK. He never had a transmission come back. Same with oil pans.
07-21-2017, 07:18 PM
#10
Melting Slicks
This will be the best $170 bucks you can spend on a auto tranny, drain plug included....
https://www.summitracing.com/int/par...2280/overview/
https://www.summitracing.com/int/par...2280/overview/
Last edited by OMF; 07-21-2017 at 07:20 PM.
07-21-2017, 08:35 PM
#12
Racer
Thread Starter
I can't find a torgue spec anywhere, is that 8-9 ft/lbs specified somewhere or what works for you? I'm just trying to be cautious, I already have 2 stripped holes.
07-22-2017, 08:51 AM
#13
Team Owner
This is just one man's opinion, take it for what it's worth. When doing a fluid change/filter replacement, many of us, myself included, get the car up off the ground, then wrestle with dropping the pan, while it still has 3-4 quarts of transmission fluid in it. As the fluid starts to exit the transmission, as we get the pan down to the last 2-3 bolts holding it in place, the fluid is seeping back into the holes where the bolts have been already removed.
When you replace the pan, this residual fluid is (usually) pushed back out by the incoming bolt, and it soaks the gasket around the hole, and this, I think, is one of the causes for the gasket to leak. Therefore, I feel that it's critical to get the bolt holes clean and dry, before re-installing the pan.
One other thing, and it's something that took me way too long to realize......The worst part of doing a fluid/filter swap, is dealing with fluid spilling from the pan, as you drop it from the car. MOST tranny pans don't have drain plugs.
A long time ago, I bought an "vacuum oil extractor", like the ones used on inboard boat engines. I forgot why I bought it, but STUPID ME....it can be used to draw most of the fluid out of the transmission, before dropping the pan, hence no messy spillage! I was always afraid of the extractor's tube loosening, and falling into the tranny. That's most likely why I didn't use it to evacuate the tranny, before dropping the pan for a filter change.
It took me way too long to realize that even if the tube fell off, it was no big deal, as I was dropping the pan anyway, to swap the filter, and at that point, the extractor tube would drop right out.
07-22-2017, 02:22 PM
#14
Racer
Thread Starter
Many of the shop manuals that have been published since the late 80s-early90s, have the torque specs in metric values. From what I've read, over the years, this works out to around 8-9 ft/lbs, and the number I successfully used on 3 vehicles that I've had, that had automatic transmissions (a '96 Z/28; a '97 S-10 4x4; and a 2005 GMC 4x4).
This is just one man's opinion, take it for what it's worth. When doing a fluid change/filter replacement, many of us, myself included, get the car up off the ground, then wrestle with dropping the pan, while it still has 3-4 quarts of transmission fluid in it. As the fluid starts to exit the transmission, as we get the pan down to the last 2-3 bolts holding it in place, the fluid is seeping back into the holes where the bolts have been already removed.
When you replace the pan, this residual fluid is (usually) pushed back out by the incoming bolt, and it soaks the gasket around the hole, and this, I think, is one of the causes for the gasket to leak. Therefore, I feel that it's critical to get the bolt holes clean and dry, before re-installing the pan.
One other thing, and it's something that took me way too long to realize......The worst part of doing a fluid/filter swap, is dealing with fluid spilling from the pan, as you drop it from the car. MOST tranny pans don't have drain plugs.
A long time ago, I bought an "vacuum oil extractor", like the ones used on inboard boat engines. I forgot why I bought it, but STUPID ME....it can be used to draw most of the fluid out of the transmission, before dropping the pan, hence no messy spillage! I was always afraid of the extractor's tube loosening, and falling into the tranny. That's most likely why I didn't use it to evacuate the tranny, before dropping the pan for a filter change.
It took me way too long to realize that even if the tube fell off, it was no big deal, as I was dropping the pan anyway, to swap the filter, and at that point, the extractor tube would drop right out.
This is just one man's opinion, take it for what it's worth. When doing a fluid change/filter replacement, many of us, myself included, get the car up off the ground, then wrestle with dropping the pan, while it still has 3-4 quarts of transmission fluid in it. As the fluid starts to exit the transmission, as we get the pan down to the last 2-3 bolts holding it in place, the fluid is seeping back into the holes where the bolts have been already removed.
When you replace the pan, this residual fluid is (usually) pushed back out by the incoming bolt, and it soaks the gasket around the hole, and this, I think, is one of the causes for the gasket to leak. Therefore, I feel that it's critical to get the bolt holes clean and dry, before re-installing the pan.
One other thing, and it's something that took me way too long to realize......The worst part of doing a fluid/filter swap, is dealing with fluid spilling from the pan, as you drop it from the car. MOST tranny pans don't have drain plugs.
A long time ago, I bought an "vacuum oil extractor", like the ones used on inboard boat engines. I forgot why I bought it, but STUPID ME....it can be used to draw most of the fluid out of the transmission, before dropping the pan, hence no messy spillage! I was always afraid of the extractor's tube loosening, and falling into the tranny. That's most likely why I didn't use it to evacuate the tranny, before dropping the pan for a filter change.
It took me way too long to realize that even if the tube fell off, it was no big deal, as I was dropping the pan anyway, to swap the filter, and at that point, the extractor tube would drop right out.
07-22-2017, 03:21 PM
#15
Team Owner
Member Since: Oct 2004
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St. Jude Donor '05
assuming the pan is flatBrown permatex>silcone
Last edited by cv67; 07-22-2017 at 03:22 PM.
07-22-2017, 05:57 PM
#16
Safety Car
"Aviation Form-a-Gasket".... I`ve used this stuff for years. It works on oil, gas, & hot water. Seals great! When it`s time to take stuff apart, it peels right off. My fil used to be the head of the motor pool in the Army, said they used it on tanks & airplanes.... so I tried it, and been using it ever since.
07-22-2017, 10:09 PM
#17
Safety Car
Make sure it aint leaking from a servo cover font seal or any area that can run down to the pans outer edge and make it appear as a pan leak. I have seen people blame the pan when it was a speedo seal .
If u are sure its the pan, be sure it is flat , lay it on a level surface with a flashlight inside pan and rotate pan around light source to check it. If t is flat . Make sure NOT to over tighten the bolts . Snug them by hand and add 1/2 to 1 full turn. Then go back and double check them.
If u are sure its the pan, be sure it is flat , lay it on a level surface with a flashlight inside pan and rotate pan around light source to check it. If t is flat . Make sure NOT to over tighten the bolts . Snug them by hand and add 1/2 to 1 full turn. Then go back and double check them.