MY 1992 4Runner has 146400 miles. Today I took it on a long trip and noticed some oil on the back of my truck. Any idea what this could be?

It is a 3.0 V6 AUTO/4x4

 

Have you looked around the engine to see if you can find any places that it could be leaking from? Any oil in the driveway?

 

I have a similar leak and wasted $$$ on valve cover seals. You might want to degrease the underside and then try and diagnose it.

I bought a metal "tray" from the local parts store to catch the oil, much cheaper.

 

Ok. I found out where the oil is coming from. It is coming from my right valve cover. I noticed that it looks like a lot of work. How much time is needed to replace the valve cover gaskets. Since my right one went bad I am also going to do the left one just to be safe.

 

I actually just replaced mine this weekend. I not going to lie its a PITA but I did it in about 5-6 hours and I changed my PCV valve and spark plugs too while I had the intake plenum off.

Check out this thread... as someone else recently did the same and put together a pretty good writeup.

https://www.yotatech.com/forums/show...&highlight=PCV

 

He..He.. Thanks for the complement. That was the write-up that I did earlier this month.

Troy

 

Try just snugging the valve cover bolts up a little, over time they sometimes work themselves loose.

 

Yeah, good call CMD! That is always a good place to start. However if the leak is on one of the many that you cant reach without taking the plenum off just go for a replace of the gasket. I got both gaskets locally for $18 and some change and the peace of mind knowing that you have have a good gasket on there once you go through all the work to take the plenum off is well worth $18 for me.

 

I'm gonna bet that the upper intake gasket will be baked on and make it very difficult to remove. Get yourself a scotchbrite wheel or an equivalent to make removal of the gasket easier. I spent about 3 hours trying to take it out with a razor blade because it was so brittle and really baked on. Make sure the scotchbrite wheel doesn't eat away at your aluminum, so check with the manufacturer for the right one. Also, if you do decide to use scotchbrite, do it before you remove the valve covers, and plug up the intake pipes with rags so that you don't get pieces of the gasket/scotchbrite into your engine. I've heard that scotchbrite can wear away at the internal parts very quickly...

Good Luck!

 

Hey thanks for the advice guys. I really appreciate it. I am going to trying tightning the bolts and clean the engine, then I will give it a week, If I see any oil there, I got my self a weekend project.