Leak diagnosis help...

Super happy to find this site!

I'm losing engine oil. I'm sure it's engine oil because when I noticed the leak, the oil was dirty and it's now clean after an oil change. Usually just a few drops each time I park it but enough that it will make a big mess in the driveway over time.

2005 Double Cab 2WD with 81k miles
5w30 Mobil One oil

I'm guessing it's the rear main seal but would appreciate some input based on these pics. Should I replace the upper oil pan gasket first? I know it's really tough to do on the 4WD trucks but what about 2WD?

Thanks,
Bob

 

Edit: Pics now showing, I was wrong, they tell a lot. Btw, cant be the oil pan seal.

 

likely rear main based off that photo. but a really bad valve cover leak could technically come down the trans and pool there too.



but likely rear main

 

Thanks, guys. I'll double-check the valve covers but when I last looked, they were dry. I just went through the valve cover mess with my T100. The edges were wet and obviously leaking, but I don't see that with this engine.

Bob

 

Valve covers are dirty but look dry from top and underneath.

Quotes I got for the rear main seal range from $800 to $1200 with dealer being most expensive.

I think I'll just do it myself. The Tundra isn't my daily, I've got a lot of wrenching experience, and I've got access to air tools, tranny jack, etc.

Besides the rear main seal, what else should replace while I'm in there? Dropping the tranny is not a job that I want to do more than once (obviously!). Looks like the output shaft seal for the tranny might be leaking, too.

 

Rear main seal $10, labor 1k

 

This kind of shit is why I don't do German cars anymore. I mean, it's grievously worse with BMWs, but I found my VWs had so many similar instances it was aggravating.

 

It’s more about auto and manual transmission

 

Right, but like, example. Neighbor had a BMW 550i. Had an oil leak somewhere, and he had a certified mechanic fix it. I'd need to ask him again on details becaus this is the perfect example and chances are I'll get it wrong. On his 550i, was early-mid 200s, maybe an 06-07? Had an oil leak he needed to have fixed, to get there it was 3.5 hours labor for the mechanic to tear the front end of the car apart.

IIRC, there was a gasket where the alternator meets the block, and it got damaged during reassembly. Mechanic fixed one leak, but that gasket issue caused another leak - which didn't make any sense to me because why would you bolt an alternator to something that required a gasket to prevent an oil leak? Certified mechanic had to come back out, another 3 hours of labor to replace a part that was like $3. He was able to dispute it with the DoorDash-like company who lined up certified mechanics and they ate the cost, but he was looking at $800 in parts and labor to replace a gasket for the alternator.

But BMW also sucked, the number of specialized wrenches and tools and BS I needed to work on my E61 was g'damn bonkers. After my 3rd lighting harness burned up (one for the front driver headlight, twice with the rear tail light completely melting apart), I sold the damn thing. I bought it b/c it was fun as hell to drive my friend's, but the minute the warranty was up, I traded it in for a fully loaded Camry. Cut my gas expenses in half. Wasn't nearly as fun to drive, but I have other vehicles for that.

Anyway, total off-tangent rant. I realize these 1GT don't have as many cases, and there's a pretty common or valid reason why. When I see it, I still reflect on the stupidity I dealt with in the German car world after owning 2 BMW and a handful of Jetta and GTIs.

 

If you're not a wrencher, old cars won't make sense. Unless you're rich. And a fool. A fool and his money are easily parted. If you can fix them, then an older car can be maintained reasonably in-expensively. I cringe when I read about people on here having to spend $3000-$5000 for repairs on trucks this old. They currently have some decent value (understatement of the year) but that may not last forever. Labor prices are crazy.....

 

First gen tundra starter is under the Intake manifold tho.

 

True, but the only ones I've ever seen shit the bed in less than 250k miles mostly killed by rodent nibbling.

 

don't you have to take the starter out to drop the tranny...
Also 81k is almost time for major service and timing belt job…

 

Timing belt/water pump/etc is on the list for Xmas break.

So far, I've got:
90311-A0002 => Rear main seal

$21 00295-00103 Formed-in-Place Oil Pan Gasket - 3 oz. Tube

00295-00103 => FIPG/Oil pan sealant (reseal it while I'm in there?)

I know I'm going to lose a bunch of fluid when I drop the tranny. When I did the driveshaft overhaul, I backed it up the driveway to prevent tranny fluid from leaking out. I guess I can open the drain plug and drain it and then measure how much came out. There's no fill hole that I can see though.

Bob

 

You should do a full tranny service, filter and gasket while you drop the tranny, since you have to drain all the fluid out and replace with new one. Filler is the dip stick hole. All serviceable tranny use dip stick hole to fill, just have to get a long tranny funnel to fill it.

 

Unless I'm missing something very obvious, this transmission does not have a dip stick. First auto trans I've had that doesn't have one.

Bob

 

You are correct. The 5 speed in the 05 and 06 do not have dipsticks. There is a drain and fill hole though. There's a good youtube video and several threads on here detailing how to drain and fill the trans.

 

it's on the side of the tranny

 

Ok, got it figured out now. Thanks for the tips.

Updated list:
90311-A0002 => Rear main seal

$21 00295-00103 Formed-in-Place Oil Pan Gasket - 3 oz. Tube

00295-00103 => FIPG/Oil pan sealant (reseal it while I'm in there?)
3533060050 => Transmission oil filter
3516860010 => Transmission pan gasket
9031143007 => Transmission output shaft seal (need to research this more)

$79 00289-ATFWS Automatic Transmission Fluid, 192 Ounces, 6 Pack

00289-ATFWS =>Transmission fluid
Beer => Guinness

Bob

 

Got under the truck today with my oxyacetylene torch and busted loose the 4 bolts holding the exhaust together behind the cats. Re-assembled with copper anti-seize. I'm not sure if I'll drop the exhaust, but I want the option and I want it to come apart easily when it is time. Truck came from salty air SF, so the bolts were treated with Loctite "rust".

 

Next step: remove the muffler. I won't have parts until next week so the truck will be a little on the loud side until then, but that's ok. Going to remove the surface rust and paint it. It actually sounds really good without it but the drone is pretty bad.

Leaving it in the front yard as a "lawn decoration". We'll see how long it takes wifey to notice.

 

She found it. Busted.

 

My truck is missing everything in this picture. It's not a daily so loud and rowdy it is, but yeah the drone sucks.

 

More clues, I think.

1. The leaking has stopped now that oil is about ⅔ of the way up from min and max on the dipstick.

2. The oil drips (about the size of a dime) we’re worse when parked in my driveway (ie, front of truck higher than rear) vs when parked on the street. (Truck level)

3. I removed the access plate from between the transmission and engine expecting to find lots of oil. There was not a lot back there.

If not filling it past ⅔ on the dipstick stops the dripping, it’s a fix that I can live with for now. Is this actually a rear main seal problem?

Bob

 

Am I confusing the Tundra with another vehicle, or was there a case where some trucks had a dipstick that was too short or too long or something? I feel like the dipstick was too short on some trucks.

If it's the case, and your truck is one of those, maybe you're over-filling your oil. That would be no bueno. But it's also possible I'm getting confused with my previous late-90s GM pickup.

 

I think there was a "short" and "long" dipstick version for this engine. I think the Sequoia 4.7 has the shorter dipstick.

I did the last oil change though and it took just over 6.5 quarts to get to the full mark on the dipstick, so I'm fairly certain that the the dipstick that I have is the right one.

It would be nice to know the lengths of the dipsticks though for comparison.