2004 LB7, RMS Replaced, Still Leaks - Diesel Truck Forum - TheDieselGarage.com
Thread Details Posted by lb7duramax, this thread has received 0 replies and been viewed 1263 times.

LinkBack Thread Tools Display Modes
post #1 of 1 (permalink) Old 01-03-2015, 09:06 PM Thread Starter
Junior Member
Join Date: Mar 2010
Posts: 2
Points: 11,915
Thanks: 0
Thanked 0 Times in 0 Posts
2004 LB7, RMS Replaced, Still Leaks

About 4 years ago my mechanic moved the crankcase ventilation hose to facilitate the install of fuel lines for a second fuel filter. He forgot to put the hose back, leaving it kinked and closed off.

I picked up the truck and once it warmed up, 6 miles down the road, I had a big cloud of oil smoke behind and with me. Mechanic said pressure had built up and blew out the RMS. He replaced the seal but thereafter the engine always had a seep, not a drip at the rear of the engine where the RMS would be the usual suspect.

Prior to this incident the engine had never leaked any oil or other fluid. I've put up with the seep as it wasn't dripping and I chalked it up to a careless job of installing the RMS under duress.
Now its a drip. Drip started after a 1500 mile trip pulling a 5th wheel. Truck has previously pulled this trailer 10000 miles since the rms replacement without dripping.
Took it to three shops for diagnosis-all pointed to the RMS as the culprit.
I had the RMS replaced with the GM part. When I picked up the truck, the mechanic was a little sheepish, saying the old RMS was in perfect shape, 'like new' and so was the crankshaft. They could see no other source of a leak when the rear of the engine was exposed.
I still have the drip, exactly as it was before. It drops about a quarter sized spot when the engine is hot and shut off. Doesn't seem to leak when running or when cold.
Went back to the mechanic.....has no answers. Put dye in the oil and ran for 10 days. Mechanic can still see no source of the oil leak. There's no leaks on the outside of the engine besides the original place.
Since it always seeped after the RMS blowout incident, I suspect some other seal/gasket was also damaged and was 'ok' for 4years but finally gave it up into a leak situation.
Anyone have any idea what else could be leaking? Thanks for your help in advance.
lb7duramax is offline  

Quick Reply

Register Now

In order to be able to post messages on the Diesel Truck Forum - TheDieselGarage.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Similar Threads
Thread Thread Starter Forum Replies Last Post
Set of 8 Injector Feed Lines for 2001-2004 LB7 #97188721 maxxis_mudder GM Parts 0 09-30-2009 10:03 PM
Water Leaks.... hhrecovery Campers 8 06-28-2009 05:17 AM
Just bought a 2004 LB7 dux5977 Duramax 2001-2004 (LB7) 8 05-05-2008 10:42 AM
2004 lb7 juice and attitude ???'s HIGH MILEAGE ELITE Duramax 2001-2004 (LB7) 3 01-15-2008 11:12 AM
TS Performance MP8 on a 2001-2004 GM LB7 wideopen Chevy - Modification instructions, Product installs and Tech Articles 0 03-09-2006 07:11 PM

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome