Internal coolant leak jeep 5.9 -
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back > Models > Jeep Grand Cherokee & Commander Forums > ZJ Grand Cherokee Forum > Internal coolant leak jeep 5.9

New Vendor - ARTEC Industries Battery MountsComplete Axle Options Expanded !!!! ECGSNEW Smittybilt Gen 2 9.5 winch at

Unread 02-19-2013, 01:41 PM   #1
Registered User
1995 ZJ 
Join Date: Sep 2012
Location: Anchorage, Alaska
Posts: 182
Internal coolant leak jeep 5.9

Ok so coolants been contaminating my oil where the two are mixing I haven't determined yet. Found this issue when trying to fix a oil pressure drop when engine is warm I replaced pump and pickup which did not help so changing the oil and adding thicker oil (20W50) which did not help pressure still dropped but noticed oil very cloudy and extremely thin. I pressure tested coolant system and test determined internal coolant leak. So my question is are these separate issues like the low oil pressure being cam bearings and I happen to have a blown head gasket, cracked head.... or the coolant and oil mixing causing the pressure drop as engine warms up?

SpenceAK is offline   Reply With Quote
Unread 02-19-2013, 04:56 PM   #2
ratmonkey's Avatar
1997 ZJ 
Join Date: Dec 2006
Location: , Pennsylvania
Posts: 19,795
continuing to run a vehicle with contaminated oil will wear out the main and rod bearings. leading to low oil pressure and eventual engine failure.
you probably have a blown head gasket or cracked head.
'97 zj 5.2, some stuff, some other suff, and some things that even work sometimes.

ratmonkey is offline   Reply With Quote

Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. is not in any way associated with Jeep or the Chrysler Corp.