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I just recall a lot of people had these truck brand new and weren't even installed right at the factory and leaking
Change rear main seal while trans is off?
- Thread starter The motor guy
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I would change it. Just had the rear main changed on the LS460. Ain't cheap
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They wanted $1400 just to drop the trans
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You would hope
That’s a tough one. If they’re know to leak then definitely replace it. If they aren’t known to leak, I’d still be inclined to change it since you’re already there…but there’s a bit of room for human error.
Someone here did a rear main (the shop did it for them) just because they were in there. It turned into quite the headache for them because it wasn’t leaking upfront, just replaced it since they were in there, then it leaked after replacement.
I guess it depends on your confidence in the guys at the shop you’re using. And that you trust they’ll use an oem part too.
Someone here did a rear main (the shop did it for them) just because they were in there. It turned into quite the headache for them because it wasn’t leaking upfront, just replaced it since they were in there, then it leaked after replacement.
I guess it depends on your confidence in the guys at the shop you’re using. And that you trust they’ll use an oem part too.
I'm certain that isn't going to stop @Trav from doing the job, and I'm positive it will be done right. I've seen him in action, he knows his craft.
Yep. @Trav will do it right. And the cost of new bolts (often specified) for the flex plate, and a new seal, added to this job is nothing compared with the cost of labor to pull the trans later and replace it.
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I'm not sure about the OP's truck but when doing the rear main on my 7.3 IDI a repair sleeve was necessary due to the seal wearing a slight groove in the crank. I know this is pretty much standard practice on the old IDI Fords but might be worth having a sleeve on hand, especially if you don't have a parts runner and the store is far away.
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Is the rear main seal all of a sudden going to dump all the oil out one day? Pretty sure it's a slow leak. I think my older cummins powered truck has a rear main seal leak. Hard to tell though when other stuff leaks too
I had a slow leak from the RMS on my 1990 4 Runner for over 100,000 miles. Never did fix it.
Modern seals typically wear slowly.
That said, a PCV system failure can blow out a seal pretty quick, though it usually takes out the weaker seals, like cam seals, first.
Modern seals typically wear slowly.
That said, a PCV system failure can blow out a seal pretty quick, though it usually takes out the weaker seals, like cam seals, first.
One other thought. It’s about $400 in parts to replace the RMS on my MB. And the seal comes in the rear main casting. Can’t get that depth wrong.
But you need new bolts for the flex plate and it’s a good idea to get new bolts for the exhaust, because that has to be dropped to get the trans out.
Adds up quick.
But will next to nothing compared with the cost of pulling the transmission.
But you need new bolts for the flex plate and it’s a good idea to get new bolts for the exhaust, because that has to be dropped to get the trans out.
Adds up quick.
But will next to nothing compared with the cost of pulling the transmission.
On the 3.slow it lives in a carrier -- I know quite a few other motors do this, too. There's a surprising amount of internet advice to not touch the carrier, which is dead wrong IMO and IME.
I did a '93 and most of the leak was from the FIPG blowing out around the carrier (evident when I removed it).
Furthermore, with the carrier plate on the bench your odds of pressing the seal in square increase ten-fold. I used my arbor press and piece of flat bar.
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Yes it's a super slow leak, but it's enough to irritate a customer if you park and drip on their clean concrete driveway.
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I stay in the street with my old 5.9 lol wouldn't dare pull into a driveway with it
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I carry a small tarp if I have to park on a nice surface.
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I don't get why people are so paranoid about their driveways. I spill oil on my shop floor, wipe it up and it's not even that noticeable after a while.
Because the driveway concrete is more porous and shows the stains. The stains do not clean up as well in a driveway. Even with a pressure washer - the stains remain.
So, parking a known leaker on my driveway, knowing it will stain the driveway, is a lot like me coming over to your house to deliberately pour a bit of red wine on your carpets.
Bet you wouldn’t like that very much.
