No oil cooler lines?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Chrismnj

Full Access Member
Joined
Sep 17, 2015
Posts
1,227
Reaction score
2,120
Location
NJ
My friend works as a mechanic at chevy, he said they were mostly installed on ppv’s
 

Rocket Man

Mark
Supporting Member
Joined
Dec 25, 2014
Posts
26,004
Reaction score
50,862
Location
Oregon
Well, I just looked at the 2002 and 2003 Suburban and Tahoe and Silverado brochures and none of them mention an external engine oil cooler for the 1500 chassis. Might it have been introduced later?
I have the engine oil cooler on my 02 Denali.
 

BG1988

Full Access Member
Joined
Nov 14, 2018
Posts
2,954
Reaction score
1,347
Can anyone chime in on why some 03-06 model year Tahoes have oil cooler lines and others don't?
I checked under my hood it was missing the Power steering,A/C compressor and alternator they had been replaced with idler pulleys
 

alpinecrick

Member
Joined
Mar 5, 2019
Posts
54
Reaction score
20
Location
Western Slope of Colorado
It's the engine oil cooling lines I'm wondering about. I've got the towing package, which equips the truck with the auxiliary transmission oil cooler on the front of the radiator to deal with the extra load on the tranny during towing. But I don't have engine oil cooling lines. Trying to figure out why some cool the engine oil and others don't.

First, lets get the GM nomenclature straight:

According to GM, the "Auxiliary Cooler" are the coolers that are located in the side tanks of the radiator. Your Tahoe has a auxiliary cooler for the trans located on the passenger side radiator tank, which then goes to the "External Cooler" (in GM nomenclature) that is located out front of the radiator and AC condenser. "Cooler" in this case is a bit of a misnomer because it is really an heat exchanger that also serves to warm the fluid for cold weather start-up, and helps to cool the fluid before flowing to the external cooler when it's hot. Helps keep the line pressure down on cold start-up among other things.

Your Tahoe should also have an auxiliary cooler for the engine oil located on the driver's side radiator tank, which does the same thing for the engine oil as it does for the trans fluid. But I've never seen a Tahoe or 1/2 ton Suburban or pickup with a factory engine external oil cooler on GMT400's or 800's. I know there was an option for them but is apparently rare. On 3/4 tons or heavier it is more common to see external engine oil coolers from the factory.
 
Last edited:

Rocket Man

Mark
Supporting Member
Joined
Dec 25, 2014
Posts
26,004
Reaction score
50,862
Location
Oregon
IMG_6391.JPG IMG_6421.JPG
First, lets get the GM nomenclature straight:

According to GM, the "Auxiliary Cooler" are the coolers that are located in the side tanks of the radiator. Your Tahoe has a auxiliary cooler for the trans located on the passenger side radiator tank, which then goes to the "External Cooler" (in GM nomenclature) that is located out front of the radiator and AC condenser. "Cooler" in this case is a bit of a misnomer because it is really an heat exchanger that also serves to warm the fluid for cold weather start-up, and helps to cool the fluid before flowing to the external cooler when it's hot. Helps keep the line pressure down on cold start-up among other things.

Your Tahoe should also have an auxiliary cooler for the engine oil located on the driver's side radiator tank, which does the same thing for the engine oil as it does for the trans fluid. But I've never seen a Tahoe or 1/2 ton Suburban or pickup with a factory engine external oil cooler on GMT400's or 800's. I know there was an option for them but is apparently rare. On 3/4 tons or heavier it is more common to see external engine oil coolers from the factory.
I have one on my Denali. It's the skinny tall one on the driver side. The trans cooler is the one in the center, and the ac condenser is behind the radiator (you can't see it in the picture). As if that wasn't crowded enough, I had to add an intercooler for the blower as well as a bigger trans cooler. I ran out of room and mounted the trans cooler behind the lower grill opening. Intercooler is in the bottom pic.

IMG_6391.JPG IMG_6421.JPG
 
Last edited:

HiHoeSilver

Away!
Joined
Feb 28, 2017
Posts
10,918
Reaction score
14,571
Location
Chicago
First, lets get the GM nomenclature straight:

According to GM, the "Auxiliary Cooler" are the coolers that are located in the side tanks of the radiator. Your Tahoe has a auxiliary cooler for the trans located on the passenger side radiator tank, which then goes to the "External Cooler" (in GM nomenclature) that is located out front of the radiator and AC condenser. "Cooler" in this case is a bit of a misnomer because it is really an heat exchanger that also serves to warm the fluid for cold weather start-up, and helps to cool the fluid before flowing to the external cooler when it's hot. Helps keep the line pressure down on cold start-up among other things.

Your Tahoe should also have an auxiliary cooler for the engine oil located on the driver's side radiator tank, which does the same thing for the engine oil as it does for the trans fluid. But I've never seen a Tahoe or 1/2 ton Suburban or pickup with a factory engine external oil cooler on GMT400's or 800's. I know there was an option for them but is apparently rare. On 3/4 tons or heavier it is more common to see external engine oil coolers from the factory.


View attachment 220281 View attachment 220283
I have one on my Denali. It's the skinny tall one on the driver side. The trans cooler is the one in the center, and the ac condenser is behind the radiator (you can't see it in the picture). As if that wasn't crowded enough, I had to add an intercooler for the blower as well as a bigger trans cooler. I ran out of room and mounted the trans cooler behind the lower grill opening. Intercooler is in the bottom pic.

View attachment 220281 View attachment 220283

Yup. Me too. I don't think there's even an rpo for it. The trans cooler has one though, and it's AUX, not external.

KNP - HD AUX TRANS. COOLING SYS

This rpo refers to the the one outside of the radiator.

20180715_201047.jpg
 

Rocket Man

Mark
Supporting Member
Joined
Dec 25, 2014
Posts
26,004
Reaction score
50,862
Location
Oregon
Yup. Me too. I don't think there's even an rpo for it. The trans cooler has one though, and it's AUX, not external.

KNP - HD AUX TRANS. COOLING SYS

This rpo refers to the the one outside of the radiator.

View attachment 220305
No RPO for mine, I decoded them all and there’s nothing about the external oil cooler.
 

Forum statistics

Threads
132,311
Posts
1,865,748
Members
96,902
Latest member
ToddYYC
Top