Cost of rear main seal replacement on an 8.3?

[vtach]

Does anyone know what it would cost to have the rear main seal replaced on and M923A2 truck? I assume it would have to go to a semi repair shop?
have a fair amount of oil leaking from the bell housing plug hole post driving.

 

[Valley Rock]

Have you had the truck a long time and this is something that's recently developed ?

Drain your oil down to the add mark on the dipstick (it won't hurt anything they have plenty of oil) and see if it makes any difference

Have no idea how much a shop would charge you to change a rear main seal, everyone's going to be different, but this may get you by for a while

 

[vtach]

Have you had the truck a long time and this is something that's recently developed ?

Drain your oil down to the add mark on the dipstick (it won't hurt anything they have plenty of oil) and see if it makes any difference

Have no idea how much a shop would charge you to change a rear main seal, everyone's going to be different, but this may get you by for a while

I have had the truck a couple of months. Changed the oil and filter when I got it, so I know the level is good. I switched to Rotella full synthetic l, maybe that was my problem. I have heard of people switching to synthetic and then developing leaks due to cleaning up sludge. I have a guy that said he can do it for $150/ hr. But he isn’t sure how long it will take.

 

[98G]

I have had the truck a couple of months. Changed the oil and filter when I got it, so I know the level is good. I switched to Rotella full synthetic l, maybe that was my problem. I have heard of people switching to synthetic and then developing leaks due to cleaning up sludge. I have a guy that said he can do it for $150/ hr. But he isn’t sure how long it will take.

This is a bigger deal than it sounds like. Personally, I'd be tempted to pour it in faster than it comes out unless you have a really bad leak.

Changing to synthetic was a bad idea. Of course you know that *now*....

The gasket/seal involving the oil pan is continuous or at least interrelated from the front timing cover all the way to the back of the block. Any tampering with any of it is likely to cause leaks elsewhere. It's like trying to eat one peanut...

I sold a truck with an 8.3 and warrantied it for the delivery transport. It developed a leak in the front cover that turned into > $5k worth of parts and labor and a complete nightmare. Of course I ended up way upside down on it....

He isn't sure how long it'll take? Two days, assuming no other problems. Shops probably charge 12-15 hours labor for it.

 

[Valley Rock]

I have had the truck a couple of months. Changed the oil and filter when I got it, so I know the level is good.

Right, so here is what I'm trying to say, according to that dipstick, which "probably" is the right dipstick for the truck, you're at the full mark .

Let some oil out to the add Mark and see if it makes any difference, I have seen the wrong dipstick in engines before and I have seen engines that literally come with a dipstick that is simply Incorrect, and it's the correct dipstick !

Some engines just find their own level, and if you let it be it'll stay there forever, and if you keep adding oil it'll keep spitting it out .

Rotella doesn't exist in anything that I own, Rotella synthetic would be my last choice for that truck or any synthetic for that matter but that's just me and I'm not going to get into why, but yes synthetic will find its way out of places that conventional motor oil will not, and straight motor oil will stay in places that multi viscosity oil will not .

If your seal has cracked and broken or the spring has fallen off of it then you're just going to change it there's no way around it, but lowering the oil level a little bit will help considerably and won't cause you any problems it has plenty of oil in it .

If you were my neighbor I'd fix it for you, it's not overly complicated you know it's just time consuming takes a little technique, I personally find the bigger stuff is the easier it is to work on and the more people will pay

 

[WillWagner]

Unlike the B, the flywheel housing doesn't need to come off. The seal is a teflon seal with a dust excluder, the installer should come with the seal, it is a white plastic sleeve that allows the seal to be bushed over the end of the crank. Early on the seals liked to wear the crank pretty bad, you'll need a speedy sleeve. BUT, the leak, 95% positive, isn't gonna be the seal, not sayin' it aint, but more than likely the seal carrier bolts are loose, the gasket hard as a rock or the main oil rifle plug is leaking. Kinda matters not, the carrier comes off to do the seal and the gasket gets replaced then, the seal centers itself that's why the carrier comes off to do the job. Torque and loctite the seal carrier bolts, make sure the carrier is flush with the block on both sides. I would also remove the main oil rifle plug and re seal it with the hardening permatex, #1 I think.

Make sure the blow by tube is clear.

I've done the whole rear on a C in a day, a bus with a giant Allison behind it, 2 days in a garbage truck....those are nasty. Bus on a set of lifts, garbage scow on the ground. Did some in backhoes, took the engine out, less than a day, Articulated loaders, a week.