To re-visit my hot water heater analogy...
You know that you're going to get hot water, you just want to make sure that your flame is not too hot, you don't want melt your water heater tank.

Okay, done.

My trans temps do not stay consistent (which, I guess, is not necessarily an issue). I am towing a 3500-4000 pound trailer. Cruising along the highway, with my new cooler installed, temps hover around 140-160. Going up hill or in town, when it kicks down to second, the temps start climbing up. Up to 220 or so. I have adjusted my bands (I am going to re-check the front band this week sometime). Am I missing something, a pump going bad, bands on their way out? Both bands were loose, several turns before I got the proper torque on them. With 66k miles on the truck, I think they they have never been adjusted before. Not a lot of gunk in the pan when I dropped it, just some black stuff (band material?).


As a side note, my trans temps run a lot cooler after the band adjustment (that is why I want to double-check it, to see if it needs a little more tweaking, help it run a little more cooler) and my mileage has gotten better. Makes sense, just something I never even considered.

Thoughts?

 

Straining uphill, when it downshifts, the TCC also unlocks, and the T/C can put a LOT of heat into the fluid. Pretty normal.

 

Good to know. I wasn't letting it go above 2500RPM's (meaning- I tried to keep my foot from getting into it too much).

 

I've boiled water in paper cups over open flames.

That's normal. Unless/until you've got a low stall converter and engine enough to twist it at lower RPM, tackle those grades at 3500-4000RPM. The converter won't dump so much heat, and you'll be in the meaty part of the power band, too.

 

I have the stock converter. I think it's rated around 1800???

In order to get those higher RPM's, it drops to second and then it starts to heat up. So you're saying to put my foot through the floor, in second, to get them higher, correct? And then it shouldn't heat up much?

 

Yep.

Once you lose third, manually shift into second and gas it enough to get engine RPM between 3,000 and 4,000. Then just lean back and enjoy the noisy ride. Don't go for third again until you can maintain road speed enough to keep converter clutch lock.

What that'll do for ya is to get your converter locked (not clutch engaged, but the locked coupling mode), cooling flow at just about the optimal rate for both engine and transmission, and the engine into it's most efficient operating region where it's making the best use of the fuel you're feeding it and producing power enough to keep you rolling along. That's the grade pulling sweet spot, and what the small block Magnum was designed to do best. It's why we have these goofy intake manifolds.

The noise of a V-8 pulling in that sweet spot frightens women, children, and dogs, but it's actually the very best (least mechanically stressful) RPM range for the entire drivetrain to be doing that kind of work. You shouldn't see excessive coolant temp on the gauge unless it's really hot out or your cooling system is fouled up. It'll climb, of course, but it shouldn't get into nervous territory.

 

Wonderful info (again, like always, from you and many other knowledgeable ones)!

 

I just spoke to a friend and he mentioned that maybe an "aftermarket TC" may make a difference in the heating up. Is he just referring to a different stall or something all-together different?

 

More than likely he's thinking of a lower stall converter. Before thinking too seriously about it, though, try pulling a grade under load with the engine spooled up into its working range. You may be quite surprised and pleased by how well it works to just let 'er run the way she's built to run -- you've got about double the horsepower at 4,000RPM as at 2,000RPM, and with the torque advantage of being in second rather than third gear it's a huge difference in pulling capacity.

You might just have more truck than you know.

 

Gotcha, and thanks again. Manually shifting to (or keeping in) 2nd is kind of a "duh" moment for me. I knew that these torque is at the higher RPM's. Why I didn't think of that, I don't know. Thinking too much about the "automatic" in the automatic transmission, I guess.