Transmission overheating

[kitkat22]

So, here is a fun topic for discussion - I have a 2014 silverado LT - 5.3L with I believe the 3.43. It is rated to tow 9600lbs. No "tow" package. I am currently about 50k miles on it.

I tow a fair amount - I have both a decently large boat and utility trailer - boat is about 7000lbs and the trailer empty is about 2000lbs - they are both used fairly regularly in the inland Northwest - there are lots of hills. About 49-50k miles, I started noticing odd noises while towing - nothing prolonged or super loud, but felt the truck was not pulling as well. Took into the dealer and requested they take a look at the transmission. It was about "ready for service" on the transmission and differentials anyway. Turns out the transmission fluid was essentially black - same with the differential fluid. Clearly getting burned and likely explains the odd noise, too. immediately after the service, the truck worked much better.

So, I am a little surprised with the transmission color - I don't feel I abuse the truck that badly - I am well below the max towing capability, I don't hard accelerate and yet here I am. The manual reports under "severe" conditions to change the transmission and differential fluid every 45k - otherwise 90k. So, I am not that far out of the window of appropriate service.

To help the situation, I am looking at a transmission cooler - relatively cheap option, especially compared to replacing/rebuilding a transmission, but I am concerned is this enough? are all 1/2 ton transmissions like this? really makes me wonder about these 1/2 tons with ability to tow >10k.

any thoughts from those with more experience? I do plan on replacing the truck in the next few years as is and with this experience may lean more to the 3/4 tons just so it survives better - or at the least get a 1/2 ton with a "tow package."

 

[Torn Mind]

Change it sooner. Recommendations are a balance between premature failure and planned obsolescence.

 

[kitkat22]

I was discussing this with a friend and we agreed that changing the fluid every 30k instead of the recommended 45k and getting a cooler would make a difference. I think given the frequency of towing I do I will likely graduate to the bigger truck. If what I am towing puts that much strain on components then it needs to be more sturdy. Thanks for the response!

 

[thecoolnessrune]

Have you looked at the Info Pages on your Gauge cluster and checked to see if you have a Transmission Fluid Temperature reading there? That will give you some real evidence if you're overheating your transmission. I know the 3500's have it, but I thought the 1500's did too. Are you seeing the Transmission Fluid Temperature warning on the truck? I think that comes on at 265 degrees. Anything consistently over 240 degrees or so (and especially 250), I'd say something needs done about it. If you're sitting in the low 200's I'd say you're doing fine.

 

[NutBucket]

IIRC the 1500 should have it too...even the lower end models without the tow package.

9600 without the tow package sounds high to me? A quick check shows I'm wrong

 

[kitkat22]

I do have the transmission fluid temp gauge on the cluster and usually don't pay attention to it. Didn't think it would have been a problem. Light never came on. I have seen in the upper 210s but nothing really that high. I have looked - there is no separate transmission cooler.

Just seems so odd - just over 45000 miles and really not that abused - ah well, live and learn.

 

[DooKey]

Like you said, if you are towing often and that towing is up and down hills then your vehicle is considered operating under severe conditions. I guess Chevy was right on the money. Since the fluid was in such poor condition it may be that you need to change the fluid a little more often.

If your transmission has a tow mode, are you using it?

 

[Gardener]

My brother-in-law, a professional mechanic, changes his truck's transmission fluid (just what's in the pan, so 1/3-1/2 of the total fluid volume) using a suction device every time he changes his motor oil. My work truck, a 3/4 ton gmc with a TH400 has needed a transmission rebuild at 60k miles of city driving, twice...lesson learned, change fluid, inspect fluid, make sure cooling system is adequate.

 

[kitkat22]

Yep - always use tow/haul mode when towing - yeah - lesson learned on this one - every 30k for sure no matter what at this point ¯\_(ツ)_/

 

[herm0016]

Are you towing in over drive? I have a 2015 and tow also, over the rockies, so generally steeper and higher elevations. No issues with mine at 100k. I pay close attention to the trans temp and manually adjust gears to keep the trans from hunting. Always use tow haul mode. 7k a lot of the time is 2500 truck territory. Max ratings are a bit of a joke. It may do it, but is it safe and can you move with traffic? Maybe not. My truck also has the factory tow package that includes the trans cooler and other bits, and the factory brake controller. I did tow about 7k cross country a few months ago, usually I am lighter though.

 

[RLGL]

Use tow/haul when towing. Definitely put a cooler on it.

 

[Torn Mind]

Like you said, if you are towing often and that towing is up and down hills then your vehicle is considered operating under severe conditions. I guess Chevy was right on the money. Since the fluid was in such poor condition it may be that you need to change the fluid a little more often.

If your transmission has a tow mode, are you using it?

Right on the money to have damage occur.

Severe severe service should be half of 45,000 based on this anecdote.

 

[herm0016]

7k on a half ton in mountians often is a lot of any half ton truck. trans temp should be monitored, fluid changed more often and it should have at least the factory tow equipment.

also, are you running a weight distributing hitch? i believe its spec in the manual for that weight of a trailer.

 

[kitkat22]

7k on a half ton in mountians often is a lot of any half ton truck. trans temp should be monitored, fluid changed more often and it should have at least the factory tow equipment.

also, are you running a weight distributing hitch? i believe its spec in the manual for that weight of a trailer.

7000lb is the cut-off for the truck for weight distributing hitch and is considered optional. I do have a tongue scale I have used and it the weight of the tongue is about 800lbs.

Sadly, I just realized with this transmission fluid change the factory tow equipment was not included. 1st truck buy - lesson learned and I know what to look for now. I do agree with everyone here, 7000lbs on a consistent basis is likely too much for any half-ton despite "max-towing" numbers. The engine may be fine, but the transmission isn't exactly built for it - especially pushing up mountain sides.

I will have fun looking