What to upgrade at 160K?

[ezdaar]

What i mean by de-oil the intake is to clean all the oil and sludge the PVC system has sprayed into it. While its off with a are sol carb cleaner.

The PVC system on (early model) ls engines is the worst designed ever.
With out a catch can and routine draining of the catch can, ls intakes quickly become saturated in oil.
Its bad bad bad for longevity and performance.

 

[jbyler]

That's a great list of stuff to update. I have an '03 Denali. I recently had 3 codes on the check engine light so replaced the 02 sensor (but I just read here that there are two 02 sensors?). Then the light came back on and it read "PO420" catalytic converter "bank 1". don't know if that's the right or left one because the mechanic said he needed to find the #1 spark plug. I also had to replace the suspension compressor and a left shock. Fairly easy. Have been ordering my parts ahead of installation from this site, which has been really great. www.newgmparts.com OEM parts but great non-dealer prices and a great discount on shipping.

I'm having noises in the rear end = "creaking" sounds, esp. over bumps and creaky sounds from the bront while backing out or turning the wheel fairly sharply (not fast, just hard turn). Any ideas on what those could be? I also have sloppy front-end steering. I'm a girl and I just don't know what these could be...didn't take my engine-rebuild class in high school...lol I tow a 23' camping trailer and just want it to be dialed in before I take it out next month... I won't know how to repair anything if I get stranded... Thanks so much.

 

[ezdaar]

Bank one is driver side.
If this mechanic needs to find number 1 plug on a LS engine. You need to find a new mechanic.
Spark plug locations, LS based engines


Creaking sounds from suspension usually equates to dry bushings.
You can use Silicone based spray lube for a quick fix.
Or go with a Lithium based grease for a longer, better fix.
OR go with this stuff to stop the creaking and squeaking for years.

As far as sloppy steering, this can be alot of things. first off and simplest to fix is the steering shaft. Link has videos and how to fix this issue.

next would be idler and pitman arm. These are a VERY common source of steering issues and are rather cheap to replace. Do both at same time I recommend MOOG parts.
Have your mechanic grease up every steering and suspension component under your Denali, it will go along ways towards quieting and removing slop.

General image showing some of the greese zerk locations. There are more.
Refer to this page for the other locations

 

[jbyler]

Bank one is driver side.
If this mechanic needs to find number 1 plug on a LS engine. You need to find a new mechanic.
Spark plug locations, LS based engines


Creaking sounds from suspension usually equates to dry bushings.
You can use Silicone based spray lube for a quick fix.
Or go with a Lithium based grease for a longer, better fix.
OR go with this stuff to stop the creaking and squeaking for years.

As far as sloppy steering, this can be alot of things. first off and simplest to fix is the steering shaft. Link has videos and how to fix this issue.

next would be idler and pitman arm. These are a VERY common source of steering issues and are rather cheap to replace. Do both at same time I recommend MOOG parts.
Have your mechanic grease up every steering and suspension component under your Denali, it will go along ways towards quieting and removing slop.

General image showing some of the greese zerk locations. There are more.
Refer to this page for the other locations

Thanks so much, Doug. (it's the owner of the shop who doesn't do the work anymore -- has someone else doing the work and he has so many cars coming in maybe at age 69 he doesn't remember them all, but I hear ya!!) This is GREAT information for me!! Thank you so much! Can't wait to print it out and get my other mechanic to do the things you've mentioned here. You are the best! xoxo

 

[JesusArTorres]

What about for the maintenance of the 4x4? What would I need to check and replace?

Last winter was the first time I used the 4x4. It sounded really loud and like it was struggling. I understand why it would sound a little louder, since more parts are moving.

Is this normal?

 

[ezdaar]

when 4x4 is engaged it will make new noises, your front tires will "skip, chirp" and generally feel very weird when making turns. This is normal.

Maintenance:
Transfer case, front and rear differentials.


Differentials:

Do a complete fluid change.
Differentials, pop the caps and clean them out, check for any metal debris.
Look for any discolored gears and or bearings. If they are dark colored, blue, purple. they have been severely over heated and should consider being replaced. altho most the time not needed.

I use mobile one 75w90 synthetic in differentials

These show the fill and drain locations.
Some of these images might not exactly reflect what is in YOUR vehical, but they will give you a good idea of what to look for.

Front


Rear, Use 3/8" socket extension to remove the plug, Must be drained by removing cover.




Transfer Case:



This is a copy and paste from a old post to save time.
Originally "Jaymans" post from another forum.

"A good way to tell if you have an AutoTrak automatic transfer case:

If you have FOUR buttons for the shift, and the top button is round and has AUTO 4WD: you have the AutoTrak and MUST use the AC Delco AutoTrak II fluid. The factory fill and the over-the-counter fluid is blue, like a Smurf.

If you have THREE buttons labeled 2HI, 4HI, and 4LO (Or whatever confusing icon GM now uses on the newer +2002 trucks): you have a regular two-speed transfer case and should use Dexron III ATF. This is red of course."





Transmission:

If you wish to do a complete 13quart fluid change, you can use "house brand trans fluid" to have a complete fluid change over and get rid of all that burnt trans fluid. This makes a substantial improvement to your transmissions shifting!
Even tho it loods red and doesnt smell burnt on the stick, Trust me IT IS.
Follow this DIY instructions.
It really requires two people to do this safely.. you want a helper to start engine and shift through the gears while YOU watch for the bubbles. This insures no damage to the trans will occur.
If you wish to do a filter change. this is the best time. follow instructions and just after pumping out the first 4 quarts. remove the trans pan as it will be empty of fluid. Then simply continue with the instructions

 

[JesusArTorres]

Got a new water pump. Does a water pump have anything to do with the coolant?

http://www.oreillyauto.com/site/c/d...ck=Search_01398_1432046_-1&pt=01398&ppt=C0331

 

[Yukonboy2014]

My Yukon has just over 256k on the clock and is still on the origional transmission and motor. Major expenses last few years:

-Alternator at 236k
-Cats at 243k
-Water pump, belt, radiator 215k
-AC Compressor @ 203k
-Fuel Pump @ 184k
-Fan clutch @163k

Those are the major repairs that I have done from 115k-current. Things just seem to start wearing out around 215k but some more some less. Truck still runs fine and has a few bolt ons. This is to just give you an idea of maintenance items that probably will go out in the next 100k or so. PCV valve has been replaced three times in mine over the years, also. All in all, these are pretty reliable machines.

Trans fluid was changed once at 163k. Rule of thumb, change it every 30k or don't change it at all. The latter seems to be working fine for me

 

[JesusArTorres]

-Alternator at 236k
-Water pump, belt, radiator 215k
-AC Compressor @ 203k
-Fuel Pump @ 184k
-Fan clutch @163k
/QUOTE]


What's the AC compressor for? Could it possibly speed up the hot air during winter?

 

[Yukonboy2014]

What's the AC compressor for? Could it possibly speed up the hot air during winter?

The AC Compressor, in a nutshell, compresses the freon in the Air Conditioning circuit, which allows for the cooling process of the air conditioner to occur but that is a long explanation that I will not get into unless you ask.

The heat in your truck comes from the engine cooling system. Hot coolant is pumped through a heater core under the dash, and the blower pushes cold air over it, and warmed air is circulated through the cabin. Your truck will not provide heat until the motor starts warming up...that's just the nature of the beast.

If you are suffering a lack of heat, I recommend checking your blend doors for proper function, as well as pulling the HVAC cover under the passenger side dash and seeing if there is a bunch of leaves and junk clogging the evaporator and the heater core. Cannot remember if your year model has HVAC air filters or not (only 99-02 did), but if it does, check that too. Search the form for a write up on the blend door actuators if you choose to see if they are working properly, there is a few good write-ups lingering around here on it.