i recently had injectors replaced and was diesel mixed in with my oil, causing it to thin out and pressure way to low. ANYway, they of course replaced the injectors but it still seems that it pressures to low for my comfort. idle is ~20 warm and cruising is around 30, maybe a little higher. in my opinion, these car dealers are no more above than the gum on the bottom of my boot

This link might help..

http://www.dieselplace.com/forum/showthread.php?t=76283

yeah i actually found that thread earlier, but thanx though. i failed to mention that i'm also getting a burn oil type of smell if you will on ocassion. whethere this is a related problem, who knows.

Well, against my better judgement, how about a little more scientific data than, "gee, it's a little low".

My truck has 12750 miles on it and at 1800 rpm's the oli pressure is ~60 lbs with the engine temp at 207°F. The oil is Delvac 1 5W-40 and there is 2432 miles on the oil and it's been in the engine since 8/05. Stock oiling system.

At idle, (750 rpms), oil pressure when warmed up is about 26 lbs.

These numbers are within spec. and is typical for a positive displacement pump, (oil pump), with a somewhat half decent oil pressure gauge.

Is that what you are seeing?

mine runs about the same temp, maybe a little lower. mileage is about 70k right now. but yeah, at idle i'm ~20 lbs and when crusing say around 2k rpms i'm not much above 30 lbs. when i romp on the throttle it will pressure up to about 60, but won't crusie their. and i don't know what red flags would come up along with a burn oil type smell.

Well, if you running about 30 psi at 2000 rpm's, I'd say that is a little low. Mine will run that at about 900-1000 rpm's. I really think that 30psig@2000 RPM's with a good gauge is unsat. But, you are talking about the dealer eating 12K if he mis-diagnosed the issue. GM does not give any bonus points to sub-standard maintenance, nor warranty money for that matter.

You might see if a dealer will show concern for the low pressure at that high of engine speed. You know that the fix is usually new bearings and I think they have been doing engine swaps and sending the long blocks back to GM for autopsy.

I would PM one of the Tech's here like Eric or Max Payne, corbra and get their opinion privately and advice on how the best way to deal with the issue.

Personally, I've always found that maintaining a good positive relationship with the service department gets better results than voicing the opinion that I wouldn't let them touch my kid's bike, even if it was true...

Check out the tech's and see what they recommend.

I would suggest a you do an oil change. who knows what they put back in after your injectors, or if they even did a change.
I have seen some fairly significant oil press changes from different manufactures or viscosity's of oil, they could have put some light weight o 5-20 in it.
Some times the KISS principal works out the cheapest.

P.S. you might have guessed I don't think much about my local stealer's abilities, although yours might have better service people than mine.:D

I would do an oil change before pursuing excess clearances on the bearings. the dealer may not use the same oil as you this may account for some of the difference and not all the oil is drained when you do a change some oil about half a qt is still in the oil cooler. and this could thin the oil slightly ( depends how contaminated your oil was with diesel fuel)

well i sure appreciate everyones help so far. this would be a real shame if this means my dmax engine is shot because of a known problem. the stealer claimed that no real damage was done when they did a compression check that i told them to do. that was my main concern whether there was any internal damage done from the thinning of the oil. so who knows...but i think its a good idea to go ahead and just change the oil for the sake of doing it...but thats good oil in there right now.

You know whats ironic...all this is starting to happen AFTER the offer to extend my warranty..go figure huh-:t

At idle I'm running at 40lbs(275Kpas). My last motor after injectors failed was less than 20 lbs. Thankfully I bought the extended warranty and all was covered.