Towing with a 4L60E

[Fless]

I'll be towing a 21-ft camper (4K lbs gross) in the near future and would like any tips for what to be alert for. I've towed slightly heavier campers in the past but that was before I had the tranny temp gauge in the cluster, and had no issues. Non-towing driving shows a warmed up temp of about 150° or so, and I will be watching that closely. I have a Diablo Sport inTune i3 and wonder if there are any settings for the tranny that I should consider using.

Truck (in my signature) has the OE transmission cooler and the fluid was changed about 15k miles ago. I'll use tow/haul mode. Generally I'll be staying at around 65mph or less unless I need to pass a Prius -- wait, I shouldn't have to exceed 65 to do that.

Anyway, do any of you transmission experts have any suggestions to minimize the wear and tear? Is there any way to tell if there is slipping between gears, or some other issue I should watch for?

TIA for your comments and recommendations.

 

[OR VietVet]

@Fless, as long as the trans temp stays below 220 degrees you should be fine. I run around town and on highway pretty hard and my trans temp gauge reads just below that 150 degree mark. I think that while pulling a long enough or big enough hill, that the trans temp could have another 20 degree window and be ok. If you are going to tow on a regular basis, I would consider adding on another tow cooler in front at the grill. Hopefully, @rockola1971 chimes in. I think his transmission suggestions and diagnosis is typically spot on.

IMO, the trans fluid being 15k miles old is another thing in your favor.

 

[Fless]

This is a pretty much once a year deal, so not too often. I'll keep monitoring the temps and if it looks like I need to upgrade the tranny cooler, I will.

Will be hauling up some high mountain passes, through the Eisenhower-Johnson Tunnels on I-70 (11,000 ft AMSL), Vail Pass, and a few others like Cottonwood Pass (12,000 ft).

 

[OR VietVet]

Been on those passes and you should be ok with the tow/haul mode. Pull over and let cool if needed.

 

[Fless]

My granddog (Stella) loves to stop for breaks! She's going with me...

 

[Scottydoggs]

ill add as long as the ass end of the trucks not sagging to hard and the trailer frame is level when hooked up should be ok.

ive got a pair of them coil air bags to keep the sag at a min with a load or trailer.

 

[Fless]

So far every time I've towed anything with some decent tongue weight the Nivomat shocks have picked it back up.

 

[rockola1971]

I use a weight distribution hitch and tow a 32ft Holiday Rambler Travel Trailer (5400lbs).

@Fless Your sig say you have 110k on the 04 Tahoe. If thats original miles then your tranny if original is getting close to the roughly 125k lay down and die date. Towing just once a year doesnt put a huge amount of stress on the tranny BUT going up and down mountains does. Check your Tahoe to see if in OD tow/haul mode if the RPM's match 3rd gear or 4th(OD) gear when in 4th(OD). I just do NOT recommend driving in 4th(OD) at all when towing on anything more than completely flat road and for the most part dont even recommend doing it then. A tranny with 110K will lose 2nd and 4th(OD) because the 2-4 band started slipping and burnt up while towing up and down a mountain. The 4L65E version and newer models are better because of the wider band and corvette type servo which produces 50%+ more holding power for the 2-4 band against the sunshell.
Whether or not the OEM tranny cooler will keep up to heat depends on the ambient temp and the grades you will driving against. As with any tranny, the cooler it runs the longer it will last. Heat will eat a tranny.

 

[YukonRog]

You don't say how many miles are on the tranny. As we all know, dirt and worn clutch materials will destroy a transmission real quick. You can change the fliud but unless you drop the pan and clean the sludge out it's not coming out in the drain. And you may have done just that. I'm just ramblin. JMHO.

 

[Fless]

Original tranny, as far as I can tell, so not quite 111k miles. The CarFax didn't have anything on it about the tranny, and I didn't get any other type of maintenance records. When I had it serviced they dropped the pan and changed the filter and fluid.