Towing Transmission Temp Question

[Sdp1234]

2004 Denali
6.0
3.73 gears
4L60-E/4L654 speed heavy duty A/trans (M32)
173K miles
Pulling about 5k total weight including wood in the truck

I was towing a camper this week. We went approx 90 miles. Highway driving @65-70 mph. Not crazy elevation but a lot of up and down hills.

Trans temp seemed to be a bit higher than normal. I typically see 180 but it seemed to stay between 210 and 220
Is his a concern?

What is the best process to check fluid levels in these trucks?

 

[bigdog9191999]

seems a little high to me, to check the fluid, pull the dipstick, it may be time for a fluid and filter change too. taking a look at the fluid can tell you a lot.

if your going to pull regularly it would probably be a good idea for an aftermarket trans cooler.

 

[Fless]

Are you using Tow/Haul mode?

Fluid level is covered in your owner's manual, available online from GM, like this from an '04:

 

[Rocket Man]

Use tow/haul and if you’re going to tow much at all get a Tru-Cool 40k and that will help a lot.

 

[Sdp1234]

Are you using Tow/Haul mode?

Fluid level is covered in your owner's manual, available online from GM, like this from an '04:

View attachment 258511

View attachment 258512

View attachment 258514

Thanks for the instructions I’ll check the levels tomorrow and have it changed when I return from vacation.

 

[Sdp1234]

Use tow/haul and if you’re going to tow much at all get a Tru-Cool 40k and that will help a lot.

Rocketman
I’m using tow haul mode and I’ll get on that aftermarket cooler in a couple weeks

Thanks

 

[Rocket Man]

Rocketman
I’m using tow haul mode and I’ll get on that aftermarket cooler in a couple weeks

Thanks

There’s lots of write ups on installing the Tru Cool 40k in our trucks.

 

[S33k3r]

There are also videos on installing the Tru Cool, along with various forums (and their members) who sell add on kits to make it even easier to install (but bring $$$).

 

[Sdp1234]

Update... I needed to tow again the next week and I was uncomfortable waiting for a cooler. I installed the only one I could get. Not anything as good as the Tru-Cool but it kept me below 180 rather than around 220. If I have to go back and replace with the Tru-Cool it will be easPictures below

 

[Sdp1234]

Next I needed to address the tapping I started hearing. Manifold bolts rusted off. Added this

Also received my headlightlight kit yesterday.

 

[S33k3r]

Do you have pictures of the manifold clamp installed?

 

[afpj]

Looks like your power steering cooler is about to go...

 

[Sdp1234]

Do you have pictures of the manifold clamp installed?

I’ll take one soon and post it

 

[Sdp1234]

Looks like your power steering cooler is about to go...

Yes, I see that. What are recommendations for replacing it. Is it hard?

 

[Sdp1234]

Do you have pictures of the manifold clamp installed?

Not easy to see but here it is

 

[Sdp1234]

Looks like your power steering cooler is about to go...

I forgot about this and the cooler went last week. I replaced it (even chose the ac delco part for more money) and the new coolerline is leaking. Can I bypass this for a few weeks until i get a chance to take the cooler out and take it back?

 

[Sdp1234]

What size is the cooler line?

 

[Mudsport96]

Not sure what the line size is, but if the transmission cooler kept temps down with the load you had, and the load is the usual you will haul...you are probably fine with it.

Also what cooler was it?

 

[avalonandl]

220 trans temp is ok. Over 250 with dexron 6 is when to be concerned.

 

[rockola1971]

Agreed. 220 deg isnt nothing to sweat bullets at BUT your tranny will last alot longer with a tranny cooler installed and temps kept below 200deg. I not only recommend them for towing vehicles but even daily drivers. They are cheap compared to the cost of a rebuild every 125k.