Engine/Transmission (1998.5 - 2002) Rear Main leak

[John Berger]

How do you know if that's what it is? I noticed black stuff coming out of the slot in the transmission Friday night after towing the 5'ver to Savannah. You could see there was a bit of spray on the exhaust as well. It didn't smell like oil and it was thicker than oil would have been. It was very black as well. It did the same thing after driving around unloaded on Saturday and on the way home. It's not enough to drip, but is a good amount, nonetheless. Other than the blowby bottle, which I do not suspect, could it be from the transmission or grease from the pilot bearing? TIA



The reason I ask about the grease is that there was a clump of what looked like moist gunk in the passenger side end of the slot of the transmission. Do the seals have a grease fitting to aid in the seal at the back of the motor?



John

 

[rkressg]

When I changed my clutch, the bottom of my bell housing was covered in this grease. I think some of this was from too much oil in the transmission and seeping out around the input shaft. Even if there is a little oil in there, I would not worry about it unless there is enough oil there to cause the clutch to slip. I doubt the rear main seal is leaking (hope it is not leaking PITA to fix), be careful it (the seal) is very large and almost $65 from Cummins.

 

[mfelix]

oil leak

I HAD OIL COMING OUT OF MY BELLHOUSING IT WAS FROM THE TRANS INPUT SHAFT SEAL. D. C. REPLACED TRANS & CLUTCH. THE USED CAR DEALER SAID HE CHANGE THE FLUIDS IN TRANS BEFORE HE SOLD IT TO ME. THATS WHY I HAD A POST ABOUT TRANS FLUID BEFORE. THINKING HE PUT THE WRONG STUFF IN THE transmission

 

[John Berger]

The problem ended up being the input shaft and the pilot bearing. This also caused the seal to start leaking. When the stock clutch grenaded on me, the truck did a lot of grinding and jerking (the service manager and I were on a test drive and we barely made it back to the lot). The hard shifting started not long after the clutch was installed. Could there have been damage to the input shaft caused by the rough ride when the stock clutch died? Bad install on the SBC, maybe? I ordered the fully splined mainshaft and 5th gear nut from Standard Transmission. The tailshaft housing has to come off to fix the seal(new RTV application) and they're going to check the innards out then. I may have them install the mainshaft at that time, depending upon the price.

 

[RustyJC]

John,



If you shelled part of the lining off the disc on your stock clutch, the imbalance could have caused the input shaft to "bow" enough to knock the front seal of the transmission out. I would have thought the front bearing of the transmission would be taken out as well if that happened, though.



Alternately, maybe some "trash" from the clutch failure made its way into the front seal and cut the sealing surface.



Rusty

 

[John Berger]

The service manager told me that there was quite a bit of up and down play with the input shaft. The stock clutch died last May. I'm happy about the leak, under the circumstances. Much better to find out about the other problem before it grenaded and caused more damage. Most likely when I would have been out of warranty. And I'm only 11. 5K from that day. I want to get a quote on installing the FS mainshaft and new 5th gear nut. Since the transmission is off of the truck for a warranty repair the service manager said it will be a whole lot cheaper to get it done now, instead of later. If the price isn't to steep, I'm probably gonna have them replace the mainshaft. I should receive it tomorrow afternoon. I thought about delivering it directly to the dealer, but this gives me a good reason to drive up that way (45 miles one way) and eyeball the transmission myself.

 

[RichB59]

Hey John,

Good idea to do the shaft and nut now while it's out, it will also give you some piece of mind knowing the won't be coming off. LOL





RichB