Hey y'all...
this is just a question in general for the 4.0.
When performing maintenance that involves seals between where oil, trans fluid, coolant flow, do you put a thin later of RTV onto the gaskets when installing or just let the gasket do it's thing and with correct torque on the bolts, no issue with leaks?
Just curious.

 

I do both as precaution as usually the metal has aged,pitted,scratched up and just not new condition anymore.

 

Use RTV only on gasket seams or with paper gaskets. For modern rubber gaskets, install them clean and dry on a perfectly clean surface. The right torque is more important than extra sealant.

 

It completely depends on the quality of the mating surfaces and the style of gasket. If the surfaces are pitted, then yes, a light film on both sides will help. If its a flat paper gasket, a super light film can help insure sealing the 1st time. Rubber ribbed gaskets like a felpro for our vale covers generally do not need anything to seal well. Its all circumstantial, and also depends on if you are the guy doing the work to your vehicle.

 

No RTV, but sometimes anaerobic flange sealant. A good gasket on a clean flat surface shouldn't need anything. On dry paper gaskets they get coated with grease.

 

In many cases the factory service manual will state whether to use any thing on the gasket or what to use and how to apply it. As stated earlier, these are older machines and mating surfaces may not be as good as once was, so that is also a consideration. Also consider that the newer better made gaskets are much improved over original gaskets. I generally try and stay with Fel-Pro, but only because I have always heard good things about them and haven't had any issues, and I have replaced almost every gasket on my Jeep over the last 28 years.

 

Thanks for the replies everyone...
Agreed... the condition of the mating surfaces would certainly play a main role in that. I tend to stay with Fel pro as I've always had good results with them.
I think the last time I did the water pump on mine I used just a light coat of RTV on the gasket just to be safe. A few weeks ago I dropped the transmission fluid pan and replaced the filter/screen while I was in there since it was 26 years old,
and I only used a small dab of RTV on the corners just to hold the gasket in place while I reinstalled the pan and with correct torque on all 19 bolts, no leaks yet. So that was good. I could tell that the pan on mine had never been off before,
so there were no imperfections or leftover RTV to get off first.