Rear Main Seal Leak/Failure 3rd Gen Tacoma

Hello Everyone,

I've got a 2016 Tacoma TRD that has developed a rear main seal leak. The leak was forming a drip underneath the transmission housing. It seemed to be collecting under the plastic cover under the transmission. The strange thing is, the truck has only 106k miles on it. Now it seems pretty unheard of from my research to see a rear main seal fail this early. When calling around I found that Toyota has come out with a replacement reinforced (metal around the edges) rear main seal for the 3rd gens. So it looks like at least Toyota knows there is an issue with the original design. Of course this doesn't help my situation as I'm over the milage warranty, and even getting warranty work done was like pulling teeth...but I'm hopping that putting this information out there may help others. I've also have had all there recommended maintenance and changed my oil religiously with the 0-20 synthetic. Almost all the miles are highway, barely any city and only a little off roading and light towing.

Here are a few pictures of what the leak looked like before taking it in. Cost of repair is between $970-$1200.

I should have some pictures of the new vs old seal from my mechanic when I get the truck back.

The first picture is after I cleaned the collected oil off.

 

Anything goes after 100k. Expect maintenance.

 

Reason I traded my truck in before 90k. There was NOTHING wrong with my truck and it ran great. That said I knew a new one would do me the same

 

Just add oil as needed. The extra oil spray will keep your frame from rusting.

 

Sorry to see this, but seals go out all the time, any mileage, any generation.

What’s the new seal part number?

I’m doing a URD clutch at some point would be good to replace the seal.

 

Is this what they meant when they say they’ve solved the rusting issue?

 

I’ll let you know the part number once I get it back from the shop. My mechanic said it’s the only one he was able to order from Toyota for the year.

 

Take a pic of the number, here’s the old one that’s been used for several years.

 

Dead on, will add its quite common in most makes too especially the front crankshaft seal.

 

Is it really that common? I've done a few google/forum searches and come up with very little.

 

It's common if the seal isn't changed as part of maintenance. The front seal on my 22R started leaking at about 120k, on the other hand the front seal on my 3.4 never leaked since it was replaced at 90k when the timing belt was replaced.

Oil seals eventually wear out on all engines or earlier if installed incorrectly. I replaced hundreds of front and rear main seals as a fleet mechanic. It was also common to repair the wear surface with a seal sleeve.

 

ive had a few of high mileage vehicles usually this happens later 150k. ive never felt compelled to have it replaced. a little bit of oil here and there about 3 inch puddle of oil every month in the garage is not something to get upset about. if you needed to get something else changed that made it a while you're in there part that makes more sense

 

My 2016 developed a rear main seal leak with under 30,000 miles. I'm trying to get it scheduled for warranty replacement. I currently have 35,000 mi on the truck. It doesn't get driven as much as I would like because I have two other vehicles. I must have the substandard seal, or there was a problem with it when they put the transmission in at the factory.

 

Bummer man. Vehicles don't like to sit though, if it's gonna sit at least fire it up for a few mins once a month.

 

It gets driven at least once or twice a week. It's not a dry rot issue for the seal. Trust me, if you look at my profile picture you'll see I have a 1989 Toyota. I've owned that truck since 1989 and about 6 years ago I pulled the engine changed head gaskets and every seal on the engine. Those seals were dry rotted. It's a seal problem on the new Tacoma. It's not a dry rot issue and it's not a worn out seal issue. Toyota put a substandard seal in these trucks.

 

Think I have same issue with my 2019 Tacoma, and just hit 106k miles as well. But have not been able to verify. Best I can tell oil is coming from plastic tab on bottom of bell housing, but my engine oil level was normal. Power steering level was low, but don’t see how it could be related.

 

have you cleaned the tab and then rechecked?

 

I did. I cleaned and then drove about 15 miles before this pic. Looks like a significant leak under there, but I guess that the wind underneath spreads around. The area pictured is the furthest forward and its dry above it. The other pic is white rag with whatever is leaking. Engine oil level still good.

 

are you still under warranty? i would think you could get this checked out. im also 19' but the area just shows dried oil on mine (at one time it leaked a little but no more) 31k miles