Improve Transmission Longevity

[Nap73]

Hey guys what’s up.

I’ve got an 04 Yukon XL SLT with 185k. Had it for a few Months now. My transmission shifts and feels fine. I was wondering if there are steps I can take to keep it that way. I’ve heard about installing a corvette servo,upgraded trans cooler, tuner etc . Does anyone have any input as to what if anything can be done to extend the life of the transmission. I’d appreciate any suggestions.

Thanks

 

[Lancem]

IMO filter change, flush, and an additional cooler would be the big 3 and the easiest to do.

 

[JonnyTahoe]

Don't pull anything.

 

[SnowDrifter]

Regular maintenance is key

Don't do any of the half ass mods like turning up the pressure valve. You'll shred your valve body

There's a TSB about installing a second magnet in the pan

Upgrade factory cooler. Trucool 40k is what I used. HPT has an install kit that's about as close to plug and play as you can get.

Bypass the factory radiator loop if you can, install a t-stat in the transmission. The radiator loop is just a heater if you're in stop and go or working with the trans. Goal is to keep temps low. I spoke with a few builders, they all told me the lower the better. Mine runs between 110 and 120. Higher than that and I flip on my radiator fans. I don't have an oil thermostat on it but it'll be on my to-do list if/when I need to replace my radiator

Corvette servo - better holding power. While you're in there, look into a pin set. Move to a longer pin if needed, there's a few YT tutorials on how to measure tolerances for the second gear band

Drive with a light foot. The v8 in these trucks has the 4l60 at its limits. Keep the torque off it

 

[Doubeleive]

I put a B&M deep pan on mine that holds a extra 2qt's and the trucool 40k. before that mine would be easy 180-205, now it runs 100-135 (winter), summer around 145 so it gave it real nice drop in temps. I also have the filter and fluid changed "annually".

 

[Nap73]

Regular maintenance is key

Don't do any of the half ass mods like turning up the pressure valve. You'll shred your valve body

There's a TSB about installing a second magnet in the pan

Upgrade factory cooler. Trucool 40k is what I used. HPT has an install kit that's about as close to plug and play as you can get.

Bypass the factory radiator loop if you can, install a t-stat in the transmission. The radiator loop is just a heater if you're in stop and go or working with the trans. Goal is to keep temps low. I spoke with a few builders, they all told me the lower the better. Mine runs between 110 and 120. Higher than that and I flip on my radiator fans. I don't have an oil thermostat on it but it'll be on my to-do list if/when I need to replace my radiator

Corvette servo - better holding power. While you're in there, look into a pin set. Move to a longer pin if needed, there's a few YT tutorials on how to measure tolerances for the second gear band

Drive with a light foot. The v8 in these trucks has the 4l60 at its limits. Keep the torque off it

I’m not doing any crazy mods. Just inquiring what others have done to help the weak transmission issue.

What would a second magnet do ?

I’ve been looking at upgrading the cooler. Thanks for the make and model. I’ll be adding this very soon.

How would I bypass the radiator loop? Are there any tutorials on this

The corvette servo is something else I’m definitely doing. What is the advantage of the longer pin?

It’s a 3rd car for me and definitely more fun to drive than any of the newer suvs I have. I’d really rather not have to “drive with a light foot” by no means am I looking to beat on it. But I’d like to be able to not have to take it easy. Short of a new trans built to address the weak points what else could I do ?

Anything else that can reasonably be done would be appreciated.

Thanks

 

[Nap73]

I put a B&M deep pan on mine that holds a extra 2qt's and the trucool 40k. before that mine would be easy 180-205, now it runs 100-135 (winter), summer around 145 so it gave it real nice drop in temps. I also have the filter and fluid changed "annually".

You think the deeper pan makes a real difference? Or is it the upgraded cooler keeping it that much cooler.

Thanks

 

[Nap73]

Don't pull anything.

The whole “sit and wait” doesn’t really appeal to Me. I’d rather try to strengthen it in some way.

Appreciated

 

[Nap73]

IMO filter change, flush, and an additional cooler would be the big 3 and the easiest to do.

I have no idea what the other owners have done regarding the trans. So I’m a little hesitant to do this. But I’m definitely going to. You see no downsides to this ?


Thanks

 

[Tonyrodz]

 

[SnowDrifter]

I’m not doing any crazy mods. Just inquiring what others have done to help the weak transmission issue.

What would a second magnet do ?
As per TSB here https://ls1tech.com/forums/attachme...350568544-new-turbo-gxp-service-bulletin-.pdf



I’ve been looking at upgrading the cooler. Thanks for the make and model. I’ll be adding this very soon.

How would I bypass the radiator loop? Are there any tutorials on this
Install flexible transmission lines, or something. It goes from trans, to radiator, to cooler, back into trans. Skip the radiator step. Only do this if you have an aftermarket cooler as the stock cooler may not be able to keep it cool enough on its own

The corvette servo is something else I’m definitely doing. What is the advantage of the longer pin?
The pin on this car is how GM adjusts band tolerances.

It’s a 3rd car for me and definitely more fun to drive than any of the newer suvs I have. I’d really rather not have to “drive with a light foot” by no means am I looking to beat on it. But I’d like to be able to not have to take it easy. Short of a new trans built to address the weak points what else could I do ?
All things I listed can be done without pulling the trans apart. You can adjust shift points a wee bit higher with a tune to keep the torque off

Anything else that can reasonably be done would be appreciated.


Thanks

 

[Nap73]

?

 

[Tonyrodz]

?

I'm sub'd to the thread.

 

[BG1988]

heat is really bad


under Ideal condition you want to keep it about minium 140f for DEXRON4 (it viscosity changes at higher temp)



95F minimum for DEXRON-6 (since it's viscosity is thin @ room temperature )

 

[Lancem]

I have no idea what the other owners have done regarding the trans. So I’m a little hesitant to do this. But I’m definitely going to. You see no downsides to this ?


Thanks

Did all three to mine at 250K miles, I had no past history on the truck at all, the fluid was dark but not burnt. Thousands of miles of heavy towing later I'm glad that I did it and I'm still going strong.

 

[HiHoeSilver]

The corvette servo is something else I’m definitely doing. What is the advantage of the longer pin?

Great read here.


https://blog.oregonperformancetransmission.com

 

[Doubeleive]

the deeper pan alone didn't do a lot temperature wise, maybe 15-20deg (which is what they claim it will do), but the added fluid capacity also helps. I think the b&m pan and the truecool max together are a good combo, I wanted to be in the 120deg area which is exactly what I got. The B&M's for the 6l80e are often on backorder it took me 3 months to get mine and I got the only one in stock then it went back to backorder again. lol, it could be different now I was trying to get mine when there were a lot of fires in the area of there business about 2 hrs from me in Santa Rosa I think Hellwig is over there as well a lot of places were closed.

 

[Doubeleive]

I added these to my truck because I am a bit rough on my vehicles, not as bad as I used to be because it just ends up coming out of your bank account, but I figured anything that will help things go a little further before breaking down is always worth it

 

[Nap73]

Did all three to mine at 250K miles, I had no past history on the truck at all, the fluid was dark but not burnt. Thousands of miles of heavy towing later I'm glad that I did it and I'm still going strong.

Ok you sold me on it. I’ll be doing this shortly

 

[Nap73]

I added these to my truck because I am a bit rough on my vehicles, not as bad as I used to be because it just ends up coming out of your bank account, but I figured anything that will help things go a little further before breaking down is always worth it

It’s the B&M Trans Pan 70392 correct?