Oil pan - Use gasket or Hi Temp Red RTV

[Gale Hawkins]

The factory offers a nice clean environment with a transmission that has never seen fluid and is probably inverted when the pan is installed. Crawling under a dirty old truck, scraping RTV or gasket material, and the steady drip, drip, drip is a little different.

Some of use have clean old trucks and we like the way RTV can help us keep them that way.

RTV is especially nice to attach a gasket so it stays in place during the install process. I like it for the valve cover to help insure it stays dry.

I still like to use a gasket when possible but use a thin glaze of RTV for security.:thumbsup:

 

[yankeerider]

Interesting - I do not drive it daily, only a few times a week (about 7k miles/yr).. So this may be the problem - what am i looking for in trying to see if it is the anti-drainback valve?

Brian

If you drive it a few times a week, I doubt that it's the issue I described. The easiest way to check is to pull the dipstick before starting the engine and see if the level is high. (The level will drop after starting because the pump will refill the converter.) You might want to check the level after it's been shut off for an hour, then after sitting overnight, etc to see if it's rising.

Another check from underneath is whether there is evidence of transmission fluid on the outside of the trans case above the pan gasket. In my situation, the pan gasket served as a "trap" for the fluid, so it looked like the leak was there, but the leakage was just pooling there before dripping off.

 

[timswi]

Sure it does....it's used in place of traditional gaskets in lots of applications. I just replaced the intake manifold gasket on my Ranger, for example. The replacement gasket doesn't even include the rubber gasket inserts that seal up the front and rear manifold-to-block gap. A tube of RTV is included and a bead is run along the top of the block after the block and manifold are cleaned and dried. As the manifold is set in place and torqued down, the excess oozes out. If there were no RTV in there, the open gap between the manifold and block would be about 1/8", and there would be oil leaks aplenty.

RTV is used in many such applications....transmission pans just aren't usually one of them. And for good reason.

What I should have said is that it's not a replacement for a gasket. I have done many intakes where you have to gob them up with RTV, but they are designed that way. I would never use RTV alone on valve covers, water pumps, tranny pans, differentials etc....They were designed to have gaskets, so I put them on.

One of the slickest things going on now is the use of O-rings instead of gaskets. The first one I ran into was on a Lumina water pump years ago..That was actually a pleasure to replace. I've seen that on lot's of other things since then and they generally don't leak.

 

[orezok]

Gee, it doesn't say anything about cleaning the surface areas. If the manual doesn't say it, I guess we don't have to do it. So much for the manual.

I thought that that would be obvious to even the most amateur mechanic so I didn't post, but here it is for those who need it.

 

[Car Doc]

One of the slickest things going on now is the use of O-rings instead of gaskets. The first one I ran into was on a Lumina water pump years ago..That was actually a pleasure to replace. I've seen that on lot's of other things since then and they generally don't leak.

Welcome to my world I absolutely agree it is the best way of all! Nearly all the covers and housings on Asian cars have been o-ringed or RTV'd for the last 30+ years (rethinking the time line gets away fast) you rarely see a Jap car leak oil because of that fwtw.

 

[jonyyuma]

Why did you have to replace it? OK, bad pump not bad O-ring. I've seen some of the O-ring installations leak because the O-ring took a set after many years. My experience with this has only been with Mopars.

The worst leaking o rings for me are behind the aircondition compressors on delco remy cars, and the o-rings in the quick connectors for the air-condition at the firewall on cars. Several brands have leaked the Freon there.But Jap orings on engines hardly leak, and on valve covers are reusable?Jy

 

[thatguy]

UPDATE - 11-8-10 - I went ahead and bought a Fel-pro gasket (instead of the RTV) to have on hand in case the hard rubber/plastic OEM gasket needed to be replaced..

After looking at the pan and seeing several places it was leaking i dropped the pan yesterday afternoon.. The OEM gasket was VERY hard and not very flexible at all, so I reinstalled the pan with the Fel-pro gasket thinking it may conform to the pan contour better..

At first the ATF dripped out of the pan at a good rate, but after tightening up the bolts a little more it finally stopped.. it looks like the pan possibly may be slightly out of square and since the OEM gasket was so inflexible the AFT was able to seep out by the gasket

thanks for all the advice

Brian

 

[Car Doc]

Did you pound the holes out backwards slightly with a tap hammer (little ballpeen) like I mentioned or even check them on a flat surface?

If not this one may leak as bad or worse, you cant properly tighten a pan that has the holes pulled in. I hope you got it but if not keep that in mind.

 

[thatguy]

Did you pound the holes out backwards slightly with a tap hammer (little ballpeen) like I mentioned or even check them on a flat surface?

If not this one may leak as bad or worse, you cant properly tighten a pan that has the holes pulled in. I hope you got it but if not keep that in mind.

I checked and none of the holes were misformed at all. I also eyeballed the entire lip (they had a rolled edge) of the pan and there was no obvious issues that i saw

As of today I had no more leaks at all.. Which is a good thing..

Brian

 

[Soundguy]

if it was a 50 yr old tractor I might make one or use the right stuff. for that nice truck.. oem gasket no questions asked.

soundguy