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Topic: Am I missing a plug on my transmission ? (Read 575 times) previous topic - next topic

Am I missing a plug on my transmission ?

I think I got (and I still do) bad fuel on my way home after the holiday. Today is the first nice day to do some work so I went about getting ready to change not two but three fuel filters.

My check engine light would come on for maybe two or three seconds, no power on slight inclines, some bucking. All of this after filling up with approx 122 gallons of diesel. I was going to ask the forum about the filters but I saw this (see photos) when I looked under the engine. I'm gonna edit after posting the photos.

These are questions guys because I'm not sure what I'm looking at.  The first two photos are the transmission, right?  The next two are the of the oil pan, right?

I see that Michelle has already answered my question with links to other posts. That was fast Michelle I have not finished my post yet. Thanks.

What concerns me is the fluid all over the oil pan. it seems to be coming from the tranny and the links suggest a seal is leaking. 

Any chance this leaking fluid could be the cause of my symptoms. I'm still changing the filters to be safe.

Ed
Ed and Michele
2000 U295  36'  (Build #5600)
8.3 ISC 350HP.
2012 Jeep Grand Cherokee (Toad)
2001 Lance Truck Camper (Sold)
2001 Lazy Daze (Class C). RK Floor Plan (Sold)

Re: Am I missing a plug on my transmission ?

Reply #1 –
Your post jogged my memory....  likely an inspection hole

Allison mystery hole

Possible missing plug
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Am I missing a plug on my transmission ?

Reply #2 –
That's some seepage from the engine rear main crankshaft seal.  My M-11 has done that for 100,000 miles.  I put a pipe plug in the inspection hole and remove it twice a year to check for seepage.  It keeps the bottom of the engine clean.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: Am I missing a plug on my transmission ?

Reply #3 –
Quote from: amos.harrison –
That's some seepage from the engine rear main crankshaft seal.  My M-11 has done that for 100,000 miles.  I put a pipe plug in the inspection hole and remove it twice a year to check for seepage.  It keeps the bottom of the engine clean.

I wholeheartedly agree, everything south of this hole is covered in fluid.  Can I get a plug from a hardware store or is it a Cummins part?

Ed
Ed and Michele
2000 U295  36'  (Build #5600)
8.3 ISC 350HP.
2012 Jeep Grand Cherokee (Toad)
2001 Lance Truck Camper (Sold)
2001 Lazy Daze (Class C). RK Floor Plan (Sold)

Re: Am I missing a plug on my transmission ?

Reply #4 –
If its on the transmission, it could also be a Allison part.  I could be wrong, but looking at the photos that looks like a common NPT thread.  I would just "eyeball" the size and go to your local Lowe's or Home Depot.  Buy 2 or 3 iron pipe plugs that look close, and give them a try.  You might get off cheap!
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Am I missing a plug on my transmission ?

Reply #5 –
Thats just a inspection hole , on some engine setups there is a tool the would go in there to lock the flywheel for servicing pullys etc on the other end.The oil looks to be a slight seep from maby rear main seal,zyou might try a gallon of Lucas oil stopleak next time you need to add oil,It does work. You do not need to plug it. Nothing up in there but flywheel and torque convertor for transmission connection.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit
 

Re: Am I missing a plug on my transmission ?

Reply #6 –
It's standard pipe thread.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R