Pumped some fuild out about 3 quarts. Then dropped pan there was still about 4 quarts dripped out into drain pan.

Dropped the pan an the filter was laying on bottom of pan. Shoved new filter into position didn’nt seam tight doe’s the pan hold this filter inplace? All previous filter I’ve changed on other GMs the car, Saab an a 1500express the filters always had to be snatched out an shoved in an where in there snuggly.

on previous filter changes this seal was jammed way up inside case this seal was in the proper hole but at the bottom of case now I was able to press the filter up to just under the inside stuff.



reinstalled pan.replenished the same amount that came out before dropping pan.

Evidently the shift linkage just snapes back on an doesn’t have the cheap plastic bushing that breaks like on the GTM360s?



Started pumping out more black fuild couple quarts at a time turning off engine then replenhishing the same amount that came out.

When I thought she was pumping cleaner fuild I stopped.



I may have pumped a bit more of the new fuild bc a bit more than 15 quarts came out.

Now I have around 15 quarts ran engine shifted though the gears an zero on the dipstick.



How low can the trans be on fuild where it shouldn’t be driven until filled to proper level? An yes I had engine running while checking level.



The express has recently been stalling out just when backing up driveway right when I shift to reverse or out driveway when shifting to drive so I crank her up again then shift again to reverse not sure if this stalling is transmission related?



I thought maybe the filter was clogged up interfering w/ shifting gears. anyway she drives excellent I did take the 250 mile one way road trip even on that black burned fuild.



Edit: I’m thinking this express’s trans pan has never been dropped. Doe’s GM recommend driving 100K miles then change the fuild an filter?



Edit2: I believe ppl that have the trans. Serviced have a pump connected an pumps out the old an pumps in the new these so called services leave the dirty filter. Is this true or false?sorry to be so long. An thanks

 

On the subject of transmission coolers. I have a 2016 3500 6.0L with 6L90 transmission.

As for transmission coolers, mine has this thing. Part 22839313. Did they ever install something beefier than this from the factory (whether with z82 package or not?) For my model year, 2016, this was all that was available - Z82 towing pkg did not include upgraded cooling.

For towing a fairly heavy trailer (7700lbs) should I upgrade? Or is this probably enough? Monitor the trans fluid temp and see how it does? I've not had any issues towing in hills but haven't gone over any big extended mountain passes just yet.

 

From what I understand that is the beefier option. Mine only has one row of fins not 2. Like this. https://www.rockauto.com/en/moreinfo...308860&pt=2088

 

I guess what I'm asking is, what is the actual capacity of this thing, at what point do I need to upgrade to something aftermarket like a Mishimoto? I don't want to burn up my transmission but spending hundreds of dollars on an aftermarket cooler that's not necessary isn't really my desire either.

The factory cooler looks like it could maybe keep pace with something like the below (link):

But nothing compared to some of the heavy duty stuff you can buy (40k coolers are massive).

I do like how the factory cooler looks so free flowing. Like it won't impede the air flow to the radiator very much. But again, I just don't want to toast my transmission.

 

I bet if you measured the length of tubes with fins on your cooler and that Derale, they would be about the same. I think that the HD Silverados had a bigger option that would bolt in the same spot. I don't tow (yet) but have been contemplating upgrading to the cooler you have when I do the fluid on the trans.

 

I've sean seriously powered upwards of 800HP at the drag stripe using the same cooler I have. matter of fact I have used this same hayden on every GM I have. you don't need a giant expensive cooler unless your towing uphill 10K LB load.

 

I would change the oil and filter and refill transmission with one quart too many. Run a clear hose from the return line to a clear gallon container. Start the engine and then shut it off After you have two quarts or so in the container. After a dozen quarts added - with your foot hard on the brakes - cycle the shifter slowly through all the gears a few times. Repeat that whole process until the ATF coming out looks like the ATF you are putting in. Usually takes about 30 quarts or so.