after about how many miles on average is it a good idea to check the valve cover gaskets for leakage/seeping of oil?

 

Not a mechanic, but long time owner. I would say only if you have a leak should you mess with taking the engine apart to check on the gaskets. But the 3.5 engine is not prone to leak, nor was the 3.0 engine - so most likely never, unless you have a leak. And even then, I would have to weigh the leak vs the expense. A drop every day is a different situation than a quart every 1000 miles.

 

What makes you ask this? I'd be looking later on when you can afford to fix your transfer case leak......I'd stop dwelling on all this weird stuff & do the basic maintenance as needed....

 

well because its happened to people before and i was just kinda wondering if there was a set amount of time per say.

 

IK you can't afford it, but if you really want to fix & do it all.....Really best to drop the cradle, Reseal the timing cover, throw a w/p at it as well as reseal the i/m, change the bank 1 coils, replace all 6 plugs, reseal the two piece oil pan, change out the vvti., fix the trransfer case leak throw a rack at it as well........Doing this is a lot cheaper then a 36/48 month loan on a gen3 of which will possibly need this done as well.......

 

Valve cover gaskets are a big money maker for repair shops.
Since most people don't keep their engines clean there is no way for a mechanic to tell how bad the leak really is but they will always quote the job if they see oil since it's gravy $$$ job.

If the engine hasn't been degreased in a long time even a slow leak can look like an urgent repair when it isn't

 

eh; no way doing all that is gonna happen. I already had all 6 plugs changed with the help of my sisters husband who is a huge diy person when it comes to their own vehicles. the second plug change wont have to happen until about 240,000 miles which i fully intend on trying to get outta this sucker and i think it will happen. Just gotta be sorta proactive when it comes to maintenance and repairs as its all part of older vehicles even ones that will just keep going and going and going like these and others. as for the steering rack; :"stealer" said there wasnt any rack leak but leaks from other places like rear main seal which there really wasnt; also the oil filter housing was leaking oil supposedly which i will address with my indy shop as they always do my oil changes. Water pump is still the oem factory one which from what ive heard can go to 200,000 plus miles and then some.

 

That's funny. Not ha ha, but ironic. I was actually looking to do most of this myself to the wife's 05 330. I'd already had the timing done per maintenance a couple of years ago by a local toyota dealer, but I do the rest myself. I need to replace the PwrSt High pressure hose as well as the rest of the PS hoses. So I figured might as well hit the rear coils and all the plugs. I also have to replace valve cover gaskets as I have a pretty severe leak from the rear one. About 2 1/2 quarts every 6 months. Weird though as i have yet to have a single drop on my garage floor. Of course, valve covers only leak while running driving, I believe.

I do also have the bank one cat code and am debating replacing it while I have everything out already. The only problem is the cat change doubles the cost of what I was doing.

I also have a very very small seep around the rack's main seal, but since I put in stop leak, I haven't had to add P/S fluid. So while I thought about changing the rack, I will probably wait since I have that Cat issue.

The two part oil pan intrigues me. I realize this is a whole different thread/conversation itself so I won't g on about it.
I will add I get all my parts from Rockauto when I have time to plan and wait.

 

I'd also check the o2 sensors as well......The 2 piece oil pan is on the 2gr's.

 

Yah, the 2 piece, lower and upper oil pans on RX350 were a first for me, but they both use FIPG (silicone gasket maker, I used Threebond spec'd in SM, been fine) instead of rubber gaskets. An extra 2 surfaces to clean and goop up, but comes apart and goes together easy enough.

 

I change the o2 sensors in 2019. But I will see if the spark plug change makes a difference first.