Engine/Transmission (1994 - 1998) Rear main seal

[1tuffram]

The rear main seal is leaking on my '95 and after getting a few repair estimates I'm considering doing the repair myself. I'm told for my 95 truck the parts I need will be the rear main seal, a gasket and a metal plate. I was told by one shop there is a kit with all the parts and the seal driver. I was also told there is a cam plug which should also be changed. Does anyone know if there has been a update to the rear main seal? Who has the best pricing for the parts? I called Cummins but they had to look into the repair based on the engine number, so I'm waiting for a return call with part numbers and pricing.

 

[toms73novass]

The cam plug is up in the head and is accessable when you drop the trany to do the rear main seal. I did not change mine.

Also, something to think about, depending on the milage on you truck, I used the kit from cummins that had the gasket and the speedy sleeve, just incase the crank has a wear pattern in it. I did not want to take the chance of it leaking again after taking out the transmission.

I also replaced my oil pan gasket since I was that far into it.

So I ordered oil pan gasket, gasket between rms housing and block and the rms and speedy sleeve kit. Just to warn you the speedy sleeve really kicks up the cost but it is good insurance.

I got good service from Maumu diesel and the price was very fair. DIESEL PARTS PRICE PERFOMANCE
They also don't need the engine # just the year dodge and they can take care of you.

Here is a link to what I was doing:

Diving in head first with my new 12v - Page 6 - Dodge Cummins Diesel Forum

 

[BigPapa]

The cam plug is up in the head

The cam plug they're referring to is in the back of the block underneath the transmission adapter plate at the end of the cam bore. Early models like your '95 have a plug sealed into the block. Later models have a square cut o-ring that seals between the block and the adapter plate. If your plug is not leaking I would leave it alone. If yours has the square cut o-ring I would replace it.



Scott

 

[toms73novass]

OOps Scott is correct, I was thinking of the freeze plug in the head.

In fact in the picture I linked it is staring me right in the face!

#ad

 

[GAmes]

The Fel-Pro seal from NAPA is the exact seal that Cummins sells except it comes with a gasket for the seal housing and costs less. I know because I compared them side by side. However, I do not know if NAPA carries a speedi-sleeve set. If time isn't an issue I would pull the trans and inspect the crank before I bought the seal.

 

[hsmith]

My leak is the oil pan. Thought the rm seal was the culprit but it was bone dry. It is also the original seal. Still haven't replaced the pan gasket, just putting up with an occasional drip.

 

[JKosten]

When you go to change the rear main make sure to have this list on hand:
Cummins rear main set (Mine had 230k and did not need a sleeve)
the two plugs that are above it in the photo to the upper left
the gasket behind the rear main housing
Tube of high quality silicone

***This is also a good opportunity to extend/replace the breathers for the transmission/transfer case to a higher location***

When I changed out my clutch and overhauled my NV4500, I also changed the rear main. I ordered all the parts before even pulling the transmission, as in the tractor dealership I work at, we have found that if a unit is due for a clutch, the rear main is another 20 minutes to change while in there. That was discovered after have a couple unit get clutches and then within 6-9 months they came back for an oil leak. Based on that experience I went into working on my own rig with the same logic: change what ever wearing parts you can while doing a job. I do not like doing a job twice because of either laziness, cheapness of lack of research.

But back to you: when you get to the seal, pull the housing it is in, change the seal on the bench and then reinstall the housing. This will allow the seal to self center on the crank as you carefully torque the housing back down.