Rear Main Seal leaking....again

[e551098]

Truck was down for about a month getting a ton of stuff done at a shop. Picked it up today and started the drive home from Winchester and about 40mi into the trip it starts to leak oil out of the bell housing.

The rear main seal was replaced as it was leaking when I got the truck. What I cannot figure out is how the seal was fine for 40mi at 60mph and then all of the sudden let loose. I picked up the new seal and carrier gasket and I figured everything should be set.


What am I missing here ?

 

[Unforgiven]

Take it back to the shop. One of the "juniors" obviously didn't install the new seal right. Have them check for gouging on the crank where the seal touches. If they JUST replaced it, then by law they will have to fix it again.

 

[davidkroberts]

 

[clinto]

Stupid question but are you 100% sure it's the rear main and not the tranny input leaking?

 

[Speddmon]

There might be a groove on the crank like Unforgivin mentioned. There is a "speedysleve" to fit the crank if this is the case. That will fix the groove by providing a new sealing surface for the seal. Or it could be that they didn't seal the carrier correctly. Either way, it's going to involve a tear-down and inspection/repair.

 

[G-Force]

When you pull the seal housing again, make sure it is modified. In [FONT=T3Font_0][FONT=T3Font_0]TM 9-2815-210-34-2-2 page 4-136, there is a drawing of the housing with additional drain holes drilled in it. Most likely it has been modified already but it can't hurt to check.[/FONT][/FONT]
[FONT=T3Font_0][FONT=T3Font_0]Here's the page from the manual. I hope this helps.[/FONT][/FONT]
[FONT=T3Font_0]Its a pdf file so right click and open in another window.
[/FONT]

 

[e551098]

There was a groove and they did get a spedisleeve to take care of it. They have an on site machine shop and they are the ones who measured. All seals on the transmission were replaced as well including gaskets.

Fluid coming out is 100% oil no doubt about it. I just dont' understand how if they did the speedisleeve and the new seal how it could be leaking again. I guess the heat from the drive 60mph ~2200rpm got it hot enough to find a problem.

Thanks for the input and yes they are taking care of it. They sent a tow truck to pick up the deuce as I was DONE at that point.

I will post up results as I love this truck, I just don;t have the equipment or space to work on heavy/invloved jobs like this.

 

[e551098]

Thank you, I will look into this !

When you pull the seal housing again, make sure it is modified. In [FONT=T3Font_0][FONT=T3Font_0]TM 9-2815-210-34-2-2 page 4-136, there is a drawing of the housing with additional drain holes drilled in it. Most likely it has been modified already but it can't hurt to check.[/FONT][/FONT]
[FONT=T3Font_0][FONT=T3Font_0]Here's the page from the manual. I hope this helps.[/FONT][/FONT]
[FONT=T3Font_0]Its a pdf file so right click and open in another window.[/FONT]

 

[G-Force]

Also, have them check the end play on the crank. I think it should be from .008 to .022 of an inch. This also is in the same TM. If you have too much crank end play it means your crank thrust bearing is worn out. That will cause the seal to go bad also.
Good Luck and let us know how you make out.

 

[e551098]

Great advice. I will report back everything. Hopefully its not a Thrust bearing because that would be just a mess...........

Also, have them check the end play on the crank. I think it should be from .008 to .022 of an inch. This also is in the same TM. If you have too much crank end play it means your crank thrust bearing is worn out. That will cause the seal to go bad also.
Good Luck and let us know how you make out.

 

[jeffhuey1n]

only thing I can come up with if all else fails (and this is based on a different application) could the recess where the seal seats be worn to the point where it's out of tolerance, i.e. the hole is too big?

 

[e551098]

Update. Thrust motion is in spec however they are reporting a lot of play up and down. I am digging into the TM so see what the spec is, but I am sure its out givin the history.

Mempis Equipment still have main bearings ?

 

[e551098]

Final update. Up and down play is outside spec. Main bearings are shot, most likely the rods are gone as well. The sad thing is I dont even hear a knock issue but the seal leaking is a sure thing. On top of it they did find coolant in the oil pan as well.

In the mean time I got a great line on a GOV rebuilt 1D motor.

If anyone needs any spare sparts off the old motor let me know. Everything else was fine.

Lesson learned: Check the tolerances on the crank when you have a leaking main seal !

 

[Murdawg]

What was the oil pressure in the truck?

 

[e551098]

30 or so while running at 2200rpm. ~10 while idle (warm)