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rcslawncare
10-26-2009, 12:02 AM
My 2003 8.1 in my truck holds about 10 lbs of oil pressure at a warm idle. Iv been told it is ok, but am unsure. The guy i know at the dealer said it was a poor design and if i buy a new one, it will have low pressure within 15000 miles or so. any ideas or truth to that?
GravelyNut
10-26-2009, 03:45 PM
My 2003 8.1 in my truck holds about 10 lbs of oil pressure at a warm idle. Iv been told it is ok, but am unsure. The guy i know at the dealer said it was a poor design and if i buy a new one, it will have low pressure within 15000 miles or so. any ideas or truth to that?
Mine runs about 15 when up to operating temp and at idle. Nothing wrong with that. Old rule was 10 PSI per thousand RPM. Your truck is likely running ~600 RPM at idle. At road speeds you should see 40+.
rcslawncare
10-27-2009, 03:22 PM
Ok, just figured it was alright. It feels a little underpowered, but it might just be getting tired. It runs 35 to 40 lbs at road speeds.
BIGBEN2004
10-27-2009, 06:49 PM
How many miles on it? I have heard good things about the 8.1 lasting a long time with few to no problems.
ZTR_Diesel
10-27-2009, 08:33 PM
Howdy - I grew up in C-U, now around Peoria. Hope the market is good in Champaign...

Not too sure of specific problems with the 8.1L. However I had a similar "low oil pressure" issue about a year back with my Dodge/Cummins. Placed an actual gauge into the 1/8" tap on top of the oil filter and checked it live cold, hot at idle & WOT. All looked fine, at least 20psi even as hot as I could get it (running idle).

Turned out it was a failing sender unit. I would suggest trying an actual pressure gauge first, and if that isn't helpful, change out the sender, it was around $25 for mine. You may need a special socket to remove and re-install the sending unit itself.

Good luck...
rcslawncare
10-27-2009, 11:36 PM
I will try that and yes, Champaign is doing great along with central IL. There's nothing but rain these days, leaves aren't very fun!! And it has 132000 on it.
pglover19
10-28-2009, 08:17 AM
Mine runs about 15 when up to operating temp and at idle. Nothing wrong with that. Old rule was 10 PSI per thousand RPM. Your truck is likely running ~600 RPM at idle. At road speeds you should see 40+.

GravelyNut.. I just PMed you... Please read....
ZTR_Diesel
10-28-2009, 06:18 PM
I will try that and yes, Champaign is doing great along with central IL. There's nothing but rain these days, leaves aren't very fun!! And it has 132000 on it.

Boy do I hear that!! Just rain on top of rain. Farmers are loving it...:cry: