Rear Main Seal Leaking? Need Second Opinion.

My truck has been great, but now at 152K I found some oil spots on my driveway last week. I looked and the oil plan/crossbar were covered in oil. It appears that the oil is coming from where the transmission meets the engine on the bell housing. There is a plastic piece on the bell housing and when I pulled it down, oil started dripping out (see picture). The valve covers and timing cover both look free of oil so I’m assuming it’s the RMS, is this a correct assumption?

 

I've not been around it or experienced it with a Tacoma but based on the Dodge 2500 Cummins diesel I had before this that had a leaking RMS I will say it looked identical to this. I'd venture to bet that is your issue. Auto or manual?

 

Thx for the reply, it's an automatic. I've never really heard of an RMS bearing going bad on a Tacoma, that's why I'm asking. I'm guessing it's going to be $$$ to replace.

 

I agree with tacoranger, never heard of a taco rms leaking, I would clean the area really well and be sure its not a valve cover or something else. You will need to pull the trans to repair the rms........good luck

 

First make sure it is engine oil and not transmission fluid.

That being said that looks like engine oil and a rear main seal. I second the opinion of cleaning it really well even up inside the bell housing area. Take it for a drive and look inside the bell housing. There isn't much to leak in there but the main seal or transmission input seal.

 

Jimmy,

Thanks for your input. It's definitely engine oil from the color and smell. I went through the engine bay and confirmed that there is no oil leaking from the valve or timing covers. I'm 99% positive it's the RMS, guess I'll have to bite the bullet and get it replaced.

 

That is rare for a Toyota. I wish you well.

 

At least yours waited for a reasonable mileage...

Mine is going in on the 30th for disassembly to fix the rear main leak, and i have 27k on it. It's under warranty, but I'm obviously wondering what was damaged or installed incorrectly from the factory.

 

Jimmy - I could substitute the word "Toyota" in the phrase "That's rare for a Toyota" for many things in my life..lol. It's a bummer for sure, but things are bound to break eventually. I've had her almost 11 years, hopefully I can keep her running for another 9.

aero - That stinks, I don't think I've ever heard of an RMS fail that early on anything. Maybe the dealer can give you some feedback on the cause.

I'm going to probably bring my truck in next week to get fixed. I'll update the forum on the actual cause and fix afterwards.

 

Had a RMS fail on a Jeep Cherokee at 9000 miles. Dealer and others could never fix it for more than a month. Ended up just let it leak until 110,000 when I traded in that POS.

 

If you are not losing measurable oil on the dipstick between changes, I wouldn't worry about changing it yet.

At this point it's just making a mess, and some periodic clean up will save your driveway. You have no clutch to contaminate, so the yuck building on the inside of the bell housing is pretty insignificant.

Cleaning and watching will also allow you to double confirm the source, which always makes one feel better about tearing into something.

Since there will be a few things dislocated to accomplish the mission when the time comes, you might consider collecting additional parts/planning additional services. Like the front trans seal, tailshaft seal, validate d shaft Ujoints are solid, trans fluid change, etc etc.

But again, if you don't have measurable loss, no reason to be in hurry-up mode.

IMHO.

 

SoCalSteve - Wow, I thought 30K was bad but 9K and they never could fix it...you have my condolences.

Bill - I've been checking my oil level, and it really hasn't dropped much. I guess a small amount of oil can really cause a mess! I called the shop and they also recommended replacing the transmission seal and some axle seals as well. I was a little confused when they said axle seals, maybe they meant tail shaft seal (I wish I would of asked more)? It's not cheap to get these replaced, but seeing fresh drops of oil everyday is getting on my nerves.

 

That is good as it is still free under warranty!

 

Mine looked like that for about 3 oil changes. No noticeable drop in oil. I just kept checking. Then the next oil change it was dry. So I've been running it about 2 yrs now and it's been dry. Could be packed full of mud though.

 

After M192 and other responses, I'm going to monitor it for the next few weeks to see if it gets any worse or better. If it gets worse I'll plan on getting it replaced.

 

I got a call from the dealership on Monday telling me that the parts for the rear leaf spring recall were in. I dropped the truck off Monday night and told them to go ahead and replace the RMS and front trans seal as well. They gave me a 2016 sr5 4runner to cruise around in for a couple days which was nice. I got the truck back last night and have put 60 miles on it since then and am happy to report the leak is gone. Hopefully the seal will hold for another 150K!

 

I'm sure that has helped your peace of mind! She's been good to you, can't neglect her!

 

So true! The new 4runner was great and all, but I'd much rather have my truck with over a decade of memories!

 

Subbed. I believe I have a rear main seal leak too...

 

Reviving an old thread wondering how much did the rear main seal change cost at the dealer??