ddana88

I have a 1999 RX300 that has an oil leak, at the point the Engine and Transmittion joins together. I can't fiqure out where the leak is coming from? Any help??

Lexmex

When you say oil, are you referring to the transmission fluid or the motor oil?

I know that transmissions can leak as thes sealant can fail at certain points, regardless of the type of vehicle.

ddana88

It looks like oil to me.

Lexmex

After looking around to find the picture I once saw, see this (not my RX though), http://www.unc.edu/~scorcher/oil_leak.jpg

In the case of transmission fluid leaking, it would be a little over to the right on the front differential behind the tranny drain plug, though I have seen tranny pans leak on other vehicles.

There are some RX owners on this forum who have had problems with the rear main seal, big $$$ when out of warranty, but I have no personal experience on this particular issue, but I know a few will chime in shortly.

salimshah

The term "oil" can be misinterpretted ... some refer to transfluid as a type of oil.

Redish tinge -> transfluid
black-gray -> engine oil.

The seam usually leaks engine oil due to "main seal" wear out.

The part itself is realtively cheap but the labor is extensive. One has to separate the trans from engine block.

I hate leaks, but there are times one has to consider living with it. specially when the leak is small and the repair is out pocket.

Salim

Tammy

Have you recently switched to a synthetic oil from a natural oil brand?

This is where the main seal in the engine will leak.

alsalih

Just as Tammy mentioned, this is the engine rear main seal. Do a search as this is a somewhat common issue on the 99-00 RX. If you did just switch to synthetic then go back to regular oil, however it's been reported even with regular oil.

ddana88

The picture look just like what the leak looks like.

Lexmex

While I never had this happen on my RX as I mentioned before, my uncle fixes both the tranny leaks and these oil seal leaks on a variety of vehicles. The reason he gets so many customers is that the agencies charge so much for labor as Salim was mentioning.

One thing you could give a try is a product called AutoRX in your oil, if you are beyond warranty.

ddana88

Have you used AutoRX or your Uncle?

Lexmex

Yes, but it does not work in every case as I will talk about below.

My uncle and I have put it into a few vehicles we buy up at the border cheap and then resell after fixing them up. However, in many cases my uncle still had to do the surgery, whether it was the tranny seal or the oil seal.

We recently had an issue with the Dodge Caravan I have been using to go to work (not a nice neighborhood) and it did not work, and my uncle ended up having to fix the tranny (had some other issues, too).

We have a friend who brings the stuff in from Texas, but he often gets redlighted by Mexican customs and we have to pay a ton more for it. This is the route I wanted to bring in the Amsoil ATF, but too risky as sometimes they confiscate the fluids he tries to bring in.

The other people that I know who have used it are friends in Mexico (successful in some cases) and my father who used it on one of his two Mercedes 190Es to clean up a tranny leak on one of the two Benzes, but on the other he had to have it resealed. Thus, it can be used in both the motor oil and in the tranny fluid.

If you want some more information on the product, see http://www.auto-rx.com, but if you want to see some more objective discussion, check http://www.bobistheoilguy.com

Lexmex

One thing that I forgot to add.

In either the case of the oil leak that is successfully plugged with AutoRX or after it is sealed, we use the Restore additive, http://www.restoreusa.com

Restore is highly helpful for compression, by my uncle also figured if it can seal up the piston walls, it can seal up cracks in other areas. I actually found this product has an extra benefit of cleaning out a gunk or deposits in the engine as everything feels really smooth after using it. He actually used some Mexican generic equivalent for years until he found this stuff to be cheaper and more effective.

TunedRX300

Lexmex,
Seems like this Auto RX is a ester based cleaner that is pretty safe. Have you tried it, for clean sludge or seal leaks?

Lexmex

I never had the issue with a leak or sludge, just on the vehicles my uncle works on.

You bring up a good point on the sludge, as my uncle has uncovered some of the stuff in some oil drains on certain vehicles using higher weight oil (more on that in a second).

I actually use a Liqui Moly engine flush to get out any gunk or varnishes, but my RX seems to have run really clean over the past 2 years or so.

I actually found the Restore product to help on the sludge a few years back. My uncle actually noticed some sulfur deposits in my oil on a change following use of Restore. Deposits probably had something also to do with my using a 15W50 Mobil 1 (they had just come into Mexico and that was the only one available) at the time, as he usually sees such deposits with higher weight oils, especially diesels truck oils. That was when Pemex gas had a much higher sulfur content even with Premium. My friend with the RX7 was using a 10W60 Liqui Moly synthetic and also encountered some sulfur deposits on his first oil change, but everything was clean after that.

Lexmex

I was thinking also about the old drain the oil and pour in the fluorescent dye trick, similar to finding PSF leaks.