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ROBERT CROSS · 08-25-2008, 07:46 PM

Quote:

Originally Posted by dano

Adonh, I just purchased a 08 Avalanche ( Same as your Suburban) and the dealer quoted a price of $350.00 plus labor for the GM Transmission cooler. The problem I have with using a B&M or equivalent product would be future warranty issues. Have you tried wiring your brake controller yet?

The only warranty issue you could have is if the cooler itself failed and or it could be proven that it was a faulty installation causing transmission failure. Dealer labor could be as much as 3.5+ hrs. Our shop is at $82.00/hr. plus fluid.
In 15yrs at GM store's I can count on three fingers the # of tranny coolers replaced. I'm well pleased with the factory unit on our 06. Last time out,fully loaded for camping we topped out at 16100#s, never went above 185*thru the Adirondacks.

It's a tough decision, especially on a 2008. Consider carefully.

wilkeytn · 08-25-2008, 08:17 PM

As I stated earlier GM part $91.00 and installation of part at Chevrolet dealer 1 hour labor. They intially told me they didnt know how much install would be, I then asked them to look up in the accessory catalog what the install time was suppose to be and it said 1 hour.

SafariSS · 08-25-2008, 08:27 PM

The other thing you will want to be sure to take care of with that 1/2 ton Burb is keeping the rear axle oil changed. On the corporate 1/2 rear axle you get a little ring/pinion that is really working it. I had a 99 several years ago and was shocked when I took the diff cover off, wow, it was like S-10 size.

I am not sure what rear end ratio you have, I had a 3.42 and it would barely pull my 3400 lb trailer through the Texas hill country and if I hit a slight headwind it was huntin' for gears.

Keep that oil changed too..

ROBERT CROSS · 08-25-2008, 08:33 PM

Quote:

Originally Posted by wilkeytn

As I stated earlier GM part $91.00 and installation of part at Chevrolet dealer 1 hour labor. They intially told me they didnt know how much install would be, I then asked them to look up in the accessory catalog what the install time was suppose to be and it said 1 hour.

I can check that out at work tommorow, I do not believe nor have I ever seen a GM tranny cooler accessory. The only ones I have experience with are factory replacements. There is a lot more work involved in installing one from scratch. The cooler lines alone are likely more than the $91.00 quoted above.

I'll run your VIN at work and see if there IS a cooler accessory for it, also what axle ratio is installed.

john hd · 08-26-2008, 05:54 AM

dittos on the oil change for the rear end.

full synth oil is cheap insurance too.

john

Silvertwinkie · 08-26-2008, 06:16 AM

A couple of thing to point out. First, this vehicle should have tow/haul mode, which IMHO would not require towing in 3rd. Second, I fully agree that trans coolers typically don't fail. In the end anything you get would be better than you have now, be it a factory install or a 3rd party. I feel the B&M coolers are far better then the OEM that the factory (or dealer) installs. The problem with some 3rd party however is that if you want the steel lines rather than plain jane rubber hoses, it can be a challenge to get a cooler that not only fits perfectly using factory mounting and lines, but the connections can sometimes be a real PITA to figure out, which for the average joe on the street who may not have sufficient skill sets to take on a project like this, makes the factory cooler a pre-engineered, drop in option that may cost less to install.

Last point is about oil changes throughout the driveline. It is imperative IMHO that all fluids in the driveline be changed at regular intervals if most of the mileage placed on the tow vehicle is mostly under severe duty, of which towing is considered severe duty in the owner's manual and factory shop books.

Now I know GM has changed some of their differentials they've installed, but if you have the 8.5" gear size in back (I don't recall the number of bolts on the cover), keep in mind that GM at one point on these installed the Auburn limited slip. Even under non severe duty I think the fluid change is between 15k to 20k miles. I've changed mine roughly every 10k or less and I have the semi-floating axle (9.5" gear set on my 3/4 ton Suburban) which is a step up from the 8.5" differential. In some applications GM DOES NOT suggest putting synthetic in the rear differential of some of the 8.5" type units. Make sure that yours is able to have synthetic put in. My 8.5" (1/2 ton equiv) installed in my GM sedan clearly suggested synthetic oil not be installed in the differential on this vehicle. I did it anyway and got lots of differential groaning sounds, even with the additional GM friction modifier required in a number of 8.5" differentials.

On a somewhat related note, I find it a good idea to add deep pan transmission pans and extended capacity differential covers. Why? More fluid takes longer to flash heat. As an example, if you place two pots on the stove, one with 1 quart of oil and the other with 2 or 3 quarts of oil, which do you think heats faster? The one with less oil. Clearly regardless of capacity the oils will reach normal operating temps, though the one with more capacity will take slight longer, it's the flash heats from towing up a good grade, or similar where the flash heat would exceed normal operating temps.

Most everything said is is sage advice and you are on the smart path for considering a trans cooler at the very least. In the end the factory engineered mechanicals will meet or exceed most of what the average owner will throw at the vehicle, but remember, most manufacturers build them out to a point. What I mean by this is they will put in a $5 part that does the job just fine, but there are $10 parts that can do a better job and may be of better design and quality. To keep their prices competitive, you might not find B & M coolers in their trucks or metal matrix composite driveshafts. These items exceed the build and the engineering. Needed? Depends on the applicationa and the end user.

In the end, a cool trans and driveline is a happy trans and driveline.

adonh · 08-26-2008, 07:46 AM

Quote:

Originally Posted by dano

Adonh, I just purchased a 08 Avalanche ( Same as your Suburban) and the dealer quoted a price of $350.00 plus labor for the GM Transmission cooler. The problem I have with using a B&M or equivalent product would be future warranty issues. Have you tried wiring your brake controller yet?

Yes I reinstalled my Jordan Brake controller. Works just fine. But I first had to figure out how to complete the connections for the GM wiring harness. Look at the pdf document in my post to this thread

http://www.airforums.com/forums/f463...ler-44321.html

This provides step by step instructions with pictures. The other issue I had was the higher receiver on the 08 Suburban. This required a new 8'drop bar for the HA.

"First, this vehicle should have tow/haul mode, which IMHO would not require towing in 3rd."

Yes the 08 Suburban does have the tow/haul mode. So with this engaged I can tow in drive, not 3rd?

Thanks

Don

wilkeytn · 08-26-2008, 08:40 AM

If someone would care to call their local Chevrolet dealer parts dept and ask them too look up part #19171483, this whole topic could be resolved much quicker. And you wouldnt have to worry about any warranty issues.

ROBERT CROSS · 08-26-2008, 02:28 PM

Quote:

Originally Posted by wilkeytn

As I stated earlier GM part $91.00 and installation of part at Chevrolet dealer 1 hour labor. They intially told me they didnt know how much install would be, I then asked them to look up in the accessory catalog what the install time was suppose to be and it said 1 hour.

I was rong, rong, rong

There is a GM tranny cooler accessory, the part # given in the previous post is valid, along with the part price.
I did some detective work today and every 1500 Burb and Silver has an oil to water cooler in the radiator. The lines that go from the tranny to the radiator are are used in the auxillary install. The out from the rad to the in on the aux, out on the aux to the in on the tranny. No one in parts or service could give me a solid quote on the labor though. There is a recommended labor on the accessory page, but the parts mgr, said the final time would depend on the punch time of the technican, the grill shell does have to be removed for the install. Otherwise it's a pretty straightforward procedure, this would probably be the best most cost effective way to get an air to oil cooler added to your Burb.
We have never stocked this accessory so check with your dealer, they may have to special order it.

Stream Safe. Bob

john hd · 08-26-2008, 03:15 PM

bob

i figured every one had a cooler, i just didn't want to chime in as you seemed to have a source to look it up.

after all it has been 8 years since i laid hands on a new truck.

i would consider a new one but mine is working to well to get rid of it!

john

adonh · 09-01-2008, 10:09 AM

I got back yesterday from my short trip with the A/S in tow. The transmission temp gauge in the 2008 Suburban indicated that the temp ranged from 190 degrees to a high of 207 degrees. The higher temps were at slow speeds in stop and go traffic. On the highway the temp leveled out at about 195 to 197 degrees.

When the trailer is not in tow the transmission temp is between 175 to 185 degrees.

Don

Silvertwinkie · 09-01-2008, 10:35 AM

Towing local road, stop and go, highway all in 95+ambient outdoor temps, I have yet to cross the 200 degree threshold. Most I have seen was 198 degrees. Were these temps with a trans cooler?

adonh · 09-01-2008, 11:34 AM

Quote:

Originally Posted by Silvertwinkie

Were these temps with a trans cooler?

No aux trans cooler, yet

Don

john hd · 09-01-2008, 11:57 AM

just for comparason, returned from iowa yesterday.

88 degrees outside, 70 mph, mostly in OD, harley in the bed, 29 excella in tow.

average 160 with one period up to 175 going up the hill east of the missisippi river.

in town about 180 after 200 miles highway.

john

ROBERT CROSS · 09-01-2008, 09:17 PM

Just got back from our Adirondack Labor Day.... 160 to 180

Don

Glad everything is is on track.

Stream Safe.

Silvertwinkie · 09-01-2008, 09:30 PM

I read this thread again tonight and decided I would crack open the Burb and take a peek at the cooler. The cooler measures 11" wide, abut 1/2" deep and 4" tall. I have to believe that GM put a cooler in that would be enough for the combined GVWR, but I have to say this thing looks REALLY PUNY.

I've hit a max of 198 degrees with mine with the ambient temps being well into the 90s, but would be a lot happier if it was at 180 degrees. I may buy a deep trans pan and have been looking at the B&M super cooler to replace the tiny trans cooler GM installed. The issue for me is that the B&Ms are 1/2" NPT connections and GM uses I believe -6AN connectors, making a swap not very easy....

mustang · 09-02-2008, 09:40 PM

pump flow rate has something to do with that also along with pan size. That alluminum finned pan is nice.

mustang · 09-02-2008, 09:41 PM

anybody use that tranny cooler with its own fan? comes as a unit

Silvertwinkie · 09-02-2008, 10:02 PM

Not yet, but I think I may add the mag-hytec pan (adds 4 quarts) and see what that does before I engineer an install for the B&M. The space is somewhat limited if I want to use the factory lines. The hood latch assembly also makes putting a much bigger one in the same place problematic. So I'll do the pan first and then if I haven't gotten down enough, will add the bigger cooler somehow. I am just totally floored that a 1/2" deep by 4" tall cooler with about 2 inches of exposed airflow from the grille is all they put in.....

john hd · 09-02-2008, 10:25 PM

twink

sounds like a lot of work for a goal of 18 degrees.

will you be happy with it in the winter? they do need to be somewhat warm to operate properly.

i did notice today mine was almost to the same temps without towing.

after talking with my neighbor who rebuilds transmissions going the full synth route is probably your best bet.

yours should be running cooler anyway, remember we removed the plugs from the bumper at norby's.

john