Rear Main Seal Leak

Greetings,

I recently purchased a 2017 Toyota Tundra with 97,000 miles from the original owner. It has factory tow package.

I didn’t do enough inspection and now realize there is a leak at the bell housing.

I have read on this forum of other Tundra owners having the same problem.

I also notice the cam tower has a slight oil residue at the back of the head on the aluminum tabs.

I have sprayed brake cleaner on the bell housing area where the oil is and then watch to see how long it takes to come back, usually a couple days.

Sometimes the oil is more prominent and sometimes it is not so noticeable, it also seems to be where the bell housing meets the engine block up a ways.

In wonder, has anyone just lived with their Tundra having a slight leak of oil at the bell housing, would there be a risk in just letting it be, especially during hot weather while towing?

I am planning to reseal the cam towers, that may fix the problem, and then it may not.

Lastly, the transmission seems to take a second or two from reverse to drive, and vice versa.

Not sure if this is good, I did a drain and fill, seemed a little better.

Maybe do another drain and fill and leave it at that, I don’t think the original owner ever had the trans serviced at 30 or 60 K as he mentioned, the trans fluid was almost black.

it’s my bad for not doing enough inspection and checking. The truck is solid otherwise, drives well, handles well, pretty clean. I enjoy driving it.

Edit: I bought an OEM PCV Valve and installed it. I sprayed brake parts cleaner on the area to clean off the oil, will see if that helps.

I paid 25k for it.

Thanks.

 

I was driving my other vehicle with RMS weeping for a few years before decided to pull the transmission and have it fixed. Luckily this job is much simpler on truck.

The only real problem with oil in that area is that it gets to the flywheel and starter. Oil attracts dust, it turns into abrasive compound, which accelerates wear of starter and flywheel.

You temporary countermeasure could be 5w30 high mileage oil, which has seal conditioners. It would not stop the leak, but may slow it down significantly.

Nice truck, SR5 DC is the best!

 

I have a slight rear main seal leak and it doesn't bother me. My old mechanic supposedly fixed it but yeah...

It's so slight I never see oil on the ground.

 

If the cam towers are leaking there is a very good chance the oil from the bell housing is from the cam towers. I’ve had the cam tower resealed 3 times by Toyota, all presented visible leaking from the cam towers and bell housing. Toyota refused to address any rear main seal leak till after the cam towers were resealed, rear main seal was not leaking and dry after cam tower reseal. Additionally, it’s really easy to fill the oil fill tube too fast during an oil change and it spills into the valley and stays in the nooks and crannies. Eventually ends up presenting as a rear main seal leak.

 

... 3 times ...

Same incompetent dudes doing V6TT rebuilds, right?

 

I've never heard of someone having to go back to re-do cam towers. Crazy. My buddy's 2017 is in the shop for cam towers and water pump. 57k miles.

 

No.

2 different trucks, current truck has been solid after first reseal. Friend of mine had to have his done twice also, it’s a shitty design.

 

https://youtu.be/HTT0sejhoOQ?si=mZzy4gjUNO16IS0x

 

Are there actual gaskets or did they do what they did to the intake valley?

 

There were a couple of years where the dowl pins that align the plate that holds the rear main seal were a wee bit too long. It wouldn't let the plate seal against the block and result in a slight oil leak. There is an updated dowl or you could just grind a touch off the old dowls.

 

Had the same as you. Purchased truck with 121k all was well. First oil change I see seep from bell housing.

I changed the PCV at that time and drained 9.4 qts of oil.

After that, no seep. Not sure if it was the PCV or over fill of oil but has been fine for 7k now.

 

Common at that mileage...PCV swap is a great thing to let her breathe and not burp thru the easiest spots...oil is cheap (kinda) and you have yourself a great truck! Treat it well and do your maintenance and it'll last forever!!

 

Engines leak oil. Most times people think its always the rear main seal. Rarely it is. 7.3 diesel is prime example.

 

Being an old shade tree mechanic from the 60’s and 70’s, I learned about the PCV Valve, I bought a new one the other day and installed it.

I cleaned the area on the bell housing to see if that fixes the issue or at least lessens it.

 

Yea, it is one of those devices that you just change whether it "jiggles" or not.

This trucks still jiggled like the new one, but apparently fixed the issue. Same with my Miata, jiggled fine but would blow clouds of blue smoke after high RPM runs until replaced.

Also, always OEM for that. Depending on the dealer it will be $12-25. I think I paid $18 for it locally.