EPayne42

Whassup Club Lexus,

I own a 1999 ES300 and have done quite a bit of work on it after purchasing it a couple weeks ago. To-date I've rebuilt the front end, replaced the steering rack, front half axles, valve cover gaskets, sparkplugs, fuel filter, air filter, several vacuum lines, changed oil & ATF + filters, and the VVTi sensors. My CEL is now off and the car is running smooth. During all of this work I noticed two drips at the bottom of the engine/trans (see pic below). I thought it may have come from the top side as the one of the VVTi sensors were leaking and the rear valve cover was leaking. I cleaned the area (and the entire engine), drove the car and now see the drips have re-appeared. Is this REAR MAIN SEAL and possibly a torque convertor seal failing? The car has 200K and seemed to have a good maintenance history until about a year ago.

Has anyone out there seen drips in this location before?

Top circle is oil and lower circle is ATF. The pan in frame is the ATF pan (to help orient you).

EPayne42

I see a lot of views, but no response on this one. I'm going to pull the transmission this weekend and take a look inside. Obviously I'll replace the seals and hopefully find the source of my mystery leak.

01LEXPL

iTrader: (10)

Is it actually DRIPPING on the driveway? If so, is it one drip per week? Day? Hour?

-Once a week, whatever, it's normal for a car this age, but ideally you would like to get changed since personally drips annoy the hell out of me.

Day/hour, well, the seals are on their way out. Two schools of thought on this one;
Fix it. Try "auto RX" or similar, like Lucas stop leak. Why? If you got nothing to lose, go ahead, if you are really **** about a 16year old car, then change it. Be forewarned, the rear main is a whole 10$ part, but its a hell of a job and a labor ***** since the subframe comes down and motor/trans are split.

Or is it just sweating? [pooling up on the trans/seal and not dripping on the ground]

Normal for all older cars. My old '01 was "sweating" like above since 75k, basically it wouldn't ever drip just collect into the same amount as your picture above. So I never cared for it, since it wasn't crucial nor was I losing fluid at all.

Follow the above as a flow-chart, and then think about your plan of action... everybody is different. Some people on this forum would take the time & money to change it all out, but that's not worth it IMO... especially with 200k on the clock!

ES300NZ

pulling the transmission for that is a over -reaction. Monitor it for a month, see how bad it really is first. park over a sheet of white paper each night .. that's the old school method.

EPayne42

It's sweating. No drops on the ground. I'm the type that hates drips and want the car to be as tip-top as possible. I know the rear main seal is a labor intensive job. This is my son's car and he'll be rolling it back to college in a couple weeks. I'd feel better knowing all leaks have been cleared up. Will be doing the timing belt as well ...just for piece of mind. I'll be replacing the cam seals and water pump (obviously). Any thoughts on doing the oil pump too? Have you done your real main seal? how about the torque converter seal?

ES300NZ

I've found fluids collect at the lowest point, so the actual source can be pretty obscure, but my money would be on a inner CV seal not a main input shaft (to gearbox) seal, could be the converter or something in the bellhousing, but it might be that it was caused by spilt top up fluids.

If I were you, I'd fix every damn thing I could before it left my reach, (including cam seals and crank seal during the cam belt job), .. but like you I'm not scared of turning a spanner.

ES300NZ

oil pump is on the crank right ? behind the timing cover? I haven't checked but unless the light it on, I'd leave it alone personally, I'm not sure but I don't think they are a known problem.

real main seal .. if the engine is cracked open (apart), do it!
.. same for torque converter seal.

must do things on my list would be these.

PVC valve. (real cam cover)
Cam cover seals & spark plug seals.
cambelt, water pump, cam seals, crank seal. idlers (2x). Tensioner.
CV boots (if worn).
bypass hose (middle of the block, big job to get too).
thermostat.
Remove sumps (pan and girdle), oil pick up & clean \ reinstall. then oil, oil filter.
replace accessory belts,

clean the air fan / heater fan (remove the dust),

thats, all folks :P

EPayne42

NICE LIST! I've done the PCV valve, cam covers & spark seals, and have dropped both the oil pan and ATF pan and cleaned and replaced gaskets, filters + fluids, and have replaced both half axles. They were shot. I replaced all the joints as well. Had a bad steering rack to swap as well.

I haven't looked at this bypass hose yet. The other items are on my checklist to be completed by next week.

Thanks!

EPayne42

Ahhhhh...I'm pretty certain the inner CV joint seals are bad. I replaced the axles, but didn't replace the seals (don't judge me...lol). I'l go back and replace these seals this weekend. I still have that oil leak...and am betting money it's the rear main seal.

Does the differential use a gear oil?

ES300NZ

... not replacing the seals might cause that, I don't normally remove the receiving cup from the transmission when I touch the half shafts / replace boots. I leave them in place to keep the fluid in the trans. If you nicked the seal with something (screw driver), or it was worn out .. disturbing seals is always a bad idea, I try and leave them alone or do the work and replace the seal too just to be sure. But, ... I like my driveway spotless cos I'm **** like that.

... it could be the rear main seal, if it is, it will only get worse and (slightly) rob the last big end bearing of oil pressure which is ... bad.

nah, the diff is part of the transaxle, so its all the same unit / same fluid / same fill up point.

EPayne42

Those seals looked pretty old. I should have swapped them when doing the axles. I didn't have the seals and really wanted to put the car back together.

This rear main seal thing is really stressing me. This job is going to be PITA. I plan to buy this: http://www.harborfreight.com/450-lb-...ack-61232.html to help move the gearbox around smoothly. Anything that will help ease lining up that trans with the engine is on my wishlist. I gotta do this job just for peace of mind. I know my son is going to be doing a lot more driving than he's leading me to believe. I don't want any preventable breakdowns.

I thought the timing belt was going to be the worst job until these leaks showed up.

Any advice on how to best insert the new axle seals?

ES300NZ

re: axle seals, the information would be in one of these three files.

ES300NZ

I have an engine lifter, and a huge truck trolley jack and a steel rolling frame,(base of an engine stand) so I tend to use the lifter to drop things, which go either onto the trolley jack which has a huge 8 inch lifting pad, or straight down onto the rolling steel frame.

The only issue I see with you proposed purchase is the way it uses a socket drive system to lift (sizzor jack), it would be kinda annoying to use. I'd get something hydraulic like this one,

http://www.harborfreight.com/800-lb-...ack-69685.html

or this one,

http://www.harborfreight.com/2000-lb...0240-9939.html

but what you propose would work fine.

Mythotical

If I were you, and I do have the equipment myself. I would just pull the engine and give it a scrub then replace all minor seals and gaskets (minor = everything but the head gaskets). Then do the timing belt, water pump, and thermostat, bypass hose, and the knock sensor sub harness as it is brittle by now and prone to damage when replacing the bypass hose. Remove the intake manifold and all of its sensors and cold tank it or just scrub it out. Do all of this and you've got a basic overhaul for this engine to go on living for another 200k. As for the transmission, 3 seals, a gasket a filter and a fluid change is all that is needed. unless it is slipping or shifting too softly. If so, it is not a hard transmission to overhaul. Simply take it apart, clean it and replace wear items. The only special tool you need is a standard long shank screwdriver with a slightly bent tip and a long hose hook for taking the c-rings out. This is a rebuild video, for an A541E, but it is very similar to the U140E.

EPayne42

THANKS SO MUCH ES300NZ and Mythotical! VERY, VERY, VERY helpful. I'll read through the guides you sent. I purchased the scissor style tranny jack. I'm going to dive in tonight. I really prefer to NOT pull the engine, but I do own an engine hoist (and have used it). If things get to difficult trying to do the job with the engine in the car, I'll just pull everything out.

I've already cleaned the engine pretty thoroughly with it in the car. I've pulled the intake when doing the valve covers and cleaned everything in sight. I haven't done the knock sensor (no codes), but did do the VVTi sensors as the car was hesitating (dying) after driving for about 20 mins. I'm very happy to see a trans rebuild is a doable task without a million special tools. I may buy one from the salvage yard and rebuild it then put it on stand-by.

I'm loving these cars more and more.