6.2 Denali oil pump replacement help / high flow unit?

[jayson]

Can anyone tell me the scope of work to replace the oil pump on my 6.2 liter?
i am aware it is located on the front of the motor behind the crank pulley.
what i am unaware of is if one needs to do any of the following:
remove timing chain cover
remove cross member
remover oil pan
remove front differential/drive terrain components

I am hopeing to do it this weekend if i dont have to tear everything in the front end apart.
if anyone has done this job or has the knowledge and will share it, that would be very help full!!!

also, do you have any suggetions on the high flow(volume) unit that can produce 33% more through the pump. I have a pretty stock motor just looking for longevity.
thanks!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

on a sub note if your looking for the detail on why i am replacing it, here is the list.
-28 F in Minnesota resulted in no oil pressure.
replaced filter and pressur sensor(clogged filter/frozen condensation).
resulted in oil pressure at operating specs.
on an 8 hour drive directly after, halp way through oil pressure dropped to 10 PSI at 2200 RPM, after passing Semi at 4400 RPM(not sure of PSI)
let motor sit for 10 minutes and received 28PSI at idle again.
I concluded that i either have shit in the oil pan and is getting sucked up by the sump, or my bypass valve on the oil pump is Sticking when i drop the hammer and get over 4000RPM(Which should be 40PSI oil pressure).

 

[Baggyp]

I'm looking for the same information. I am noticing inconsistencies with oil pressure, but I have good compression. Hopefully someone will have some input!!

 

[sennister]

I'm looking for the same information. I am noticing inconsistencies with oil pressure, but I have good compression. Hopefully someone will have some input!!

What year is your Denali?

Just throwing this out there. If it is an 07-08 take a look into Cam Bearing Problems. The 6.2 engines in these years have had issues with the Cam Bearings in either 2009 or 2010 (don't remember which but think it was 09) they made some engine changes one of which was a change to the cams to address this issue as well as add AFM and larger injectors to support E85. We were looking at Escalades and Denalis and I was happy to have found the 2011 that we ended up getting because this issue was resolved by then.

The symptom is low oil pressure which can be the all too common sending unit issue or in the case of the early 6.2's the cam bearing issue. Unfortunately while there has been some cases where I have seen repair work (cam replacement) done to resolve the issue, I have also read of reports of complete engine replacement. I guess it depends on how long you run assuming it is a bad sending unit when it is actually more serious. The best way to tell is to throw a new sending unit on there (assuming the new one is good as well) or use a manual pressure gauge.

http://www.cadillacforums.com/forum.../567098-low-oil-pressure-shut-off-engine.html

Edit:

http://en.wikipedia.org/wiki/GM_small-block_engine#Generation_IV_.282005.E2.80.93current.29

The L92 was modified with Flex Fuel capability for MY 2009 and became the L9H, and was further modified with Active Fuel Management for MY 2010 (and becoming the L94) in the Cadillac Escalade and GMC Yukon Denali's.

Like I said in there somewhere was a cam modification as well. Not sure if it is in the L9H or L94.

 

[Baggyp]

Thanks for the information!!

I do have an 07 and the symptoms definitely fit the cam shaft. I guess I am going to look into replacing the cam (bearings) to start.

 

[jayson]

Thanks for the information!!

I do have an 07 and the symptoms definitely fit the cam shaft. I guess I am going to look into replacing the cam (bearings) to start.

Here is the issue that i had. the LS3 (6.2) liter's have a filter screen under the oil pressure switch. According to the gentleman at the GM dealer, they last about 100k and it time for a replacement or cleaning.
You can remove the switch and the screen if your a badass and have specialty tools (oil switch socket, impact swivel, long Pick) and some SMALL HANDS!!! if you do not have these items and don't feel like hurting yourself trying, there is an easier way. ask me how I know....... SOB!!!
The easier way is to take off the intake manifold and access the oil pressure switch and filter screen that way. It takes a little more time to remove some of the components, but sooo much less stress on your body. couple special tools needed: 90 or 45 degree pick, fuel line connector separator, service manual for intake plenum torque specs and sequence.
If you go on to a GM parts direct site you can see the diagram of where the oil switch is located.
After changing this out all my oil pressure problems went away.. I was getting prepared to change the oil pump and timing set.
the parts guy also explained doing this is a RARE occurrence and he couldnt even recall having to change a timing set or oil pump on the LS3 motors. the Cam issue may have some symptoms but it was described to be with the cylinder deactivation and E85... could be wrong though.

Please pass this along if individuals here are having oil pressure problems and not hearing lifter chatter... I thought for awhile i had a huge issue and it was a $15 filter screen.

 

[NateDiggity]

I know this thread is a bit old but I'm hoping it catches someone's eye. I have had these same problems and tried to replace the sending unit to help.

My question is though, how far in or "deep" does the filter below the sensor sit? I pushed my pick all the way in (3-4" depth) and never felt anything. Unless on some oddball chanec I got it And it fell off the pick down on the bell housing or something before I could see it.... I did it without removing anything.


Or is it a better chance that someone pulled it out trying to get better oil pressure/fix a bigger issue (oil o ring, weak pump etc)