[Toyota3.0V6Forever]

Hi, I bought my 1992 3vze toyota extended cab back in january and it had the top end of the motor rebuilt at 110,000 miles. It has been running great and reliable. I always keep the rpm below 3,500 and monitor the oil. I recently switched to synthetic (2 months ago), the motor has only 50,000 miles on rebuild. I parked it in the garage yesterday and i see that its leaking oil. Not alot, and it looks to have just started. Only small drips once the truck has stopped running. It seems to be coming from around the transmission area on the back of the engine. The truck has no loss in power, and starts right up. Does not smoke, the oil and engine temperatures are right in the middle. Im saddened and worried about my truck, I love it, i hope its nothing serious, but does anybody have any idea what this could be? I just had surgery and i wont be able to look under the hood for a couple weeks, so i wanted to get some pointers on where to look before i really start digging in. Thanks alott!!!

 

[V62WDLongbed]

Sounds like the rear main seal has started to leak. Using a high mileage oil may help, but don't count on it.

 

[Toyota3.0V6Forever]

Sounds like the rear main seal has started to leak. Using a high mileage oil may help, but don't count on it.

Thanks for the reply! So it could be the thinner viscosity of the synthetic oil seeping through the seals? I guess i knew i ran the risk of that. Time to face the consequences, What do you recommend? Drain immediately and switch back to regular weight? Ive only used this synthetic once.

 

[killer01Ws6]

I am a big fan of synth oil, it is best to use it on a new engine or right after the rings seat on a rebuilt one... What weight had been ran in the truck after the rebuild? what did you go with on the synth?
Yes high mileage oils can help seals with additives they put in them, but quality synth or dino oil will do the same if changed on time and the vehicle does not sit for a long time without running.

Said all of that to get to this.. unless you went to a thinner weight... it is not caused by the synthetic oil.

 

[V62WDLongbed]

If you have a manual transmission I would say yes, change the oil to either conventional or high mileage ASAP. This may buy you some time before the leak causes the clutch to slip.

If you have an automatic you could wait until the next time you would normally change the oil before trying something different.

 

[Toyota3.0V6Forever]

If you have a manual transmission I would say yes, change the oil to either conventional or high mileage ASAP. This may buy you some time before the leak causes the clutch to slip.

If you have an automatic you could wait until the next time you would normally change the oil before trying something different.

Nuts im confused. Im talking about engine oil. I never even touched the transmission, i think the oil is coming down from the back of the engine.

 

[Toyota3.0V6Forever]

I switched from a 10-30w conventional to a 10-30w FULL synthetic.

 

[V62WDLongbed]

The rear main seal is between the engine and the transmission. What will drip out is motor oil. If you have a manual transmission this oil will find it's way to the clutch and flywheel.

 

[killer01Ws6]

The rear main seal is between the engine and the transmission. What will drip out is motor oil. If you have a manual transmission this oil will find it's way to the clutch and flywheel.

He is correct, if you have a stick... the oil leak will eventually get to the clutch and it is toast at that point.. it will not get better or can't be cleaned.

 

[TOYOPARTSMAN]

killer01Wso6 is absolutely correct. Also, if you have a manual Trans, if you do pull the trans to replace the rear main seal, I'd recommend changing the front trans seal and clutch at that time. Unless you just replaced the clutch, it will go bad. And if you do decide to replace the clutch, Take my adivice on this, "get the flywheel surfaced" to many people skimp on this parts and it ends up biting them in the you know what later.

 

[kamesama980]

I'd just get a new flywheel. rockauto and other places have them for $50-100 and it'll run you $50+ to get the flywheel cut.

If you do get it machined, make sure you get it step-cut like stock. the clutch I just towed 5k lbs with couldn't go over 20% throttle in my cressida with a non-stepped flywheel (was resurfaced without the step). same clutch disk, same pressure plate, new flywheel with the step. .020" matters!!!

 

[Jayota]

I got mine resurfaced when I did my clutch, didn't cost much really. Around $35-40..

 

[TOYOPARTSMAN]

I guess we are all in agreement, whatever you do, don't just put the old one back in. You need to either buy a new one, or have yours resurfaced. Personally speaking, I'd have mine resurfaced.

 

[mickeydim468]

I am not convinced it is his rear main seal...

Is the oil getting on top of the tranny? If so, it isn't the main seal, it would most likely be a bad valve cover gasket.

Let us know.

Mike!

 

[sb5walker]

It's true you will need to do a bit more investigating to know what's leaking. If the oil is near the joint between the motor & bell housing, the most likely sources of leak are rear main seal or valve cover gasket/camshaft plug, as has been mentioned. Gear oil leaks would likely be further back.

Since the leaking appears to have started after you switched to synthetic, there may be a connection. You didn't mention which synthetic you're running. Makes a big difference. Castrol Edge tends to be very thin for it's rated weight - I'd avoid it for both the 22re & 3vze. Mobil is now using cheap Group III basestock in their Mobil 1 product and it loses viscosity almost as fast as mineral oils. So either of them would be more likely to cause leaks. Other synthetics might leak if they tended to have thinner viscosity. You need to investigate the 100 deg C viscosity of the oil you're using. If less than 12 cSt, it may be contributing to your leaking and I would use something thicker.

The two main benefits to synthetic oil are that it flows at lower temperatures, and it resists viscosity breakdown, which means it can go longer between changes. A good quality conventional oil lubricates just as well, but not for as many miles.

Valvoline MaxLife is a high-quality synthetic blend that resists viscosity breakdown for nearly as long as the Group III full synthetics such as Pennzoil Platinum, Valvoline Synpower and Castrol Syntec. It resists breakdown LONGER than Mobil 1. And MaxLife has more seal-swelling esters that will probably slow down your leak. So it's worth a shot, imo. I started using MaxLife 10W-40 this spring in my 285k mile veezy and it did slow down leaks in my front & rear main seals.

Certainly if you have a higher mile motor with leakage issues, you should use a heavier oil than 10W-30. I recommend trying MaxLife 10W-40 to see if it helps. In the summer, you could even try 20W-50, or a mix of 20W-50 & 10W-40.

 

[Toyota3.0V6Forever]

Thanks for all of the replys, I did use valvoline full synpower 10-30w as my oil for my truck. I think the problem may be a headgasket, i just find all of this surprising because the headgasket job was done only 50000 miles ago. i think The oil does drip from above the transmission behind the motor. Only in small puddles, one - three drips after each start up, then it stops.

 

[Jayota]

It could also be a rear cam cover gasket. Or simply the back of the valve cover.

Its pretty easy to not put RTV in the right spots on the valve cover gasket and it will start to leak.

 

[fourwd1]

pay attention to V62WD and SB5Walker's responseses, they are the most probabel

 

[denniswoo]

My advice is this, If you started with a petrolatum based oil then never switch it. I live in an area where the temps in summer average about 90 deg. I have always used 10/40 Valvoline oil in my engine 22re until I decided to change to castrol 10/40 about 2 years ago. Now im not much on advertisement but since I have switched brands of oil I have not been using any oil for it to be of any concern. I was using between half quart and quart with the other brand between changes, the oil seems not to be so dark now when I change it either. My engine has 179k on it and I change my oil at or close to 3k regularly.

 

[Toyota3.0V6Forever]

Hey guys, thanks for the help and advice. Turns out, after i went for a ride in it around the block and parked it back in the garage, it wasn't leaking any more. I put some cardboard underneath, no drips. The leaking has stopped. To make sure of this, i started my truck every day for a couple of days and still no leaking. I dont know what kinda truck leaks for about a week then stops... I guess She's got some female human like characteristics. (Menstrual period) Lol, maybe i should check back once a month and see.