Keeping coolant and transmission temps under control when towing in the summer heat

[alpha_omega]

Do you have the K5L rpo?

No, I do not have the K5L rpo.

I think it was in conjunction with those models that had a trailer brake or those with the larger rear end.

 

[alpha_omega]

I think you are correct. This is why I was asking way back when this thread first started whether an updated alternator was needed for the 700w fan motors. I guess one could potentially verify with the RPO code, cross referencing a vehicle they know came stock with the 700w’s and see what alternator pkg came standard.

KW1 GENERATOR,160 AMP
KW2 GENERATOR,124 AMP
KW3 GENERATOR 135 AMP
KW5 GENERATOR 220 AMP
KW7 GENERATOR 170 AMP
KW8 GENERATOR 155 AMP
KW9 GENERATOR 190 AMP
KXB GENERATOR,DUAL,100 AMP
KX7 GENERATOR 270 AMP
KYU GENERATOR 200 AMP
KZT GENERATOR,DELCOTRON 60 AMP
K09 GENERATOR,120 AMPERE
K22 GENERATOR,94 AMPERE
K26 GENERATOR 40 AMP
K32 GENERATOR, 95 AMPERE
K60-99 (too many to add, and I’m not sure if they apply to the North American Yukon’s, Hoes or Denalis).

 

[RooTBeeRthe1st]

I think you are correct. This is why I was asking way back when this thread first started whether an updated alternator was needed for the 700w fan motors. I guess one could potentially verify with the RPO code, cross referencing a vehicle they know came stock with the 700w’s and see what alternator pkg came standard.

KW1 GENERATOR,160 AMP
KW2 GENERATOR,124 AMP
KW3 GENERATOR 135 AMP
KW5 GENERATOR 220 AMP
KW7 GENERATOR 170 AMP
KW8 GENERATOR 155 AMP
KW9 GENERATOR 190 AMP
KXB GENERATOR,DUAL,100 AMP
KX7 GENERATOR 270 AMP
KYU GENERATOR 200 AMP
KZT GENERATOR,DELCOTRON 60 AMP
K09 GENERATOR,120 AMPERE
K22 GENERATOR,94 AMPERE
K26 GENERATOR 40 AMP
K32 GENERATOR, 95 AMPERE
K60-99 (too many to add, and I’m not sure if they apply to the North American Yukon’s, Hoes or Denalis).

I think I shared my build codes. I have 160 amp alternator and 700 watt fans factory

 

[Fless]

I think I shared my build codes. I have 160 Watt alternator and 700 watt fans factory

Let's hope your alternator is 160 AMPS. Doh!

 

[Doubeleive]

ran it a little hard today and yesterday in 100deg ambient weather @100mph and above she likes to hang around 203-205deg's at sea level
I'm thinking I will pick up a fan kit like this, comes with everything including a thermocouple switch that turns on at 180 and shuts off at 165
it's generic and that's fine if it holds up for a while. It's a puller by default but can be reversed as well.

 

[gooffeyguy]

ran it a little hard today and yesterday in 100deg ambient weather @100mph and above she likes to hang around 203-205deg's at sea level

203-205 trans or engine Temps?

 

[Doubeleive]

203-205 trans or engine Temps?

transmission, engine doesn't budge I would like to keep the transmission no higher then 180, if it's getting over 200 just on flat land then pushing it up a mountain it's going to go somewhat higher

 

[gooffeyguy]

I was gonna say that those seem like normal engine Temps, but wasn't sure which you were talking about.

Last week when it was in the mid to upper 90s here and the high humidity had the heat indexes in 105-110, my trans Temps were consistently in the 165-167 when on highway and 175 when in town

 

[Doubeleive]

I was gonna say that those seem like normal engine Temps, but wasn't sure which you were talking about.

Last week when it was in the mid to upper 90s here and the high humidity had the heat indexes in 105-110, my trans Temps were consistently in the 165-167 when on highway and 175 when in town

mine does ok just putting around it will stay under 200 but if I push it hard it goes up, since it was re-built for 500hp it runs about 15-20 deg higher than it used to then putting it down below it gets less air, the fan kit looks pretty simple to install the tru cool is 8.5 X 22 and the 2 fans are 9" each so should fit just right

 

[Geotrash]

transmission, engine doesn't budge I would like to keep the transmission no higher then 180, if it's getting over 200 just on flat land then pushing it up a mountain it's going to go somewhat higher

200+ is normal for the 6L80. Those temp vs transmission life charts floating around the internet are for 1970s era fluids and transmissions.

 

[RooTBeeRthe1st]

200+ is normal for the 6L80. Those temp vs transmission life charts floating around the internet are for 1970s era fluids and transmissions.

You're really not supposed to run the fluid cooler than 180f I've heard

 

[Doubeleive]

heat kills, and I drive it hard. I can make a transmission and stock cooler hit 230-240 just driving, I am happy it's not getting that high currently but I would like it to stay a little bit lower. My 03 Silverado would sit at 180 all day no matter what I did to it and all it had was whatever the small portion of the radiator cooler it used.

 

[mikeyss]

You're really not supposed to run the fluid cooler than 180f I've heard

I have owned my Tahoe for 4 years and I drive 10 miles round trip to work. My trans only ever gets between 100 - 140 degrees in that short drive. This was even when I had the stock cooler. My trans shows no issues with this, and I've only changed the fluid once when I put in my stall converter. I still only see 140 in the city with 100 degree outside temps.

 

[Geotrash]

I have owned my Tahoe for 4 years and I drive 10 miles round trip to work. My trans only ever gets between 100 - 140 degrees in that short drive. This was even when I had the stock cooler. My trans shows no issues with this, and I've only changed the fluid once when I put in my stall converter. I still only see 140 in the city with 100 degree outside temps.

All I can say is that I've changed *my* frame of reference for transmission fluid temps based on all of the reading I've done over the past couple of years. I tried to set up my transmission cooling system this year so that it would stay between 175ºF and 200ºF for 90% of all of the driving I do, and not exceed 235ºF in any but the most extreme circumstances while towing our camper. I'm sure you'll have no problems running cooler than what GM technically recommends. I've seen nothing that explains *why* they recommend it, only that they do.

 

[Geotrash]

heat kills, and I drive it hard. I can make a transmission and stock cooler hit 230-240 just driving, I am happy it's not getting that high currently but I would like it to stay a little bit lower. My 03 Silverado would sit at 180 all day no matter what I did to it and all it had was whatever the small portion of the radiator cooler it used.

Yeah, my '02 Suburban ran cooler, too. These 6L80s definitely run a lot warmer. Fingers crossed that we'll be able to keep ours cool on our upcoming big trip out west!

 

[alpha_omega]

Are you guys running headers or stock manifold? If headers do you have them wrapped? What about your trans cooler lines?

 

[Geotrash]

Are you guys running headers or stock manifold? If headers do you have them wrapped? What about your trans cooler lines?

Stock manifolds, stock cooler lines for both the engine and transmission, with the exception of the mods I made to place the Derale cooler into the transmission cooling circuit.

 

[RooTBeeRthe1st]

Are you guys running headers or stock manifold? If headers do you have them wrapped? What about your trans cooler lines?

Sad stock manifolds
Haven't touched the lines.

 

[Doubeleive]

stock manifolds, lines are stock up to where the factory cooler was. but maniac behind the wheel.

 

[Tozan]

How long do these transmissions average in miles before rebuild or replacement?