# Allison 3060 fluid leak



## AC7880 (Oct 11, 2008)

I have a Allison 3060 6 speed transmission on a 94 Bluebird BMC motorhome Spartan Chassis hooked to a Cummins 8.3 300 HP.

It is leaking (seeping) fluid from the dipstick, and the electrical harness cover at the front end (front of coach end) of the trans.  I understand there are O-rings on the dipstick into the trans, and under the electrical plug cover.

I am mechanically inclined.  Is this a owner do-able fix, or does it need a pro?  Will I need to drain the trans first (fluid above these items)?  Do I need to purchase o-rings from allison, or can I just pull them, then match them up for size at a auto parts house?

Thanks for any advice,
Dan


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## utmtman (Oct 11, 2008)

Re: Allison 3060 fluid leak

It is not hard to do.  Yes I would drain some of the tranny fluid or be ready to have it flowing when I pull the dipstick tube.  I dont know if you can find the o ring at a parts house but you could call first to find out.  You might find one at a truck parts house for big trucks for sure.    Good luck to ya.


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## dbarton291 (Oct 11, 2008)

RE: Allison 3060 fluid leak



> AC7880 - 10/11/2008  8:56 AM
> 
> I have a Allison 3060 6 speed transmission on a 94 Bluebird BMC motorhome Spartan Chassis hooked to a Cummins 8.3 300 HP.
> 
> ...



The dipstick is easy.  The dipstick tube is retained to the main case by one self tapping screw.  The short Allison-supplied dipstick tube can just be pulled out once that screw is removed and the dipstick tube seal usually stays in the main case.  It's a seal, not a simple o-ring.  If the OEM has put their own dipstick in, their may be more fasteners to the power package that have to be removed before the dipstick tube can be taken out to replace the seal.

For the second leak, I'm not sure what you mean by an electrical plug cover.  If you're referring to the main transmission harness connector where the chassis wiring harness goes into the transmission, replacing that connector O-ring involves dropping the control module.  That's not something most owners tackle.


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## AC7880 (Oct 11, 2008)

Re: Allison 3060 fluid leak

Thanks for the info,
Dan


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## PLYMOUTH1962 (Oct 31, 2008)

RE: Allison 3060 fluid leak

DAN I HAVE THE SAME LEAK AT THE HARNESS.DID YOU GET YOURS FIXED? IF SO HOW HARD WAS IT? 
THANKS 
LARRY THOMASON


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