TIMMY22

I was towing a load today, probably too heavy?

with the O/D off...

A 5 ton trailer that probably weighs 2500#'s with a 6500# tractor.

Starting from an intersection at the bottom of a big hill. It shifts from first to second then it will rev up to about 2100 rpm or so and she just chugs up the hill real slow (25-30mph) doesn't shift even if I really press the pedal. seems like im picking up speed until about half way then it seems to slow down a little even though the rpm hasn't changed.

once I crest the hill, she will shift into 3rd then 3rd lockup. the next hill is not bad because it will stay in 3rd lockup especially if I build alot of speed.

there are no symptoms of this when i'm not towing or towing the trailer empty.

i don't mind going slow, the people behind me were not happy.



normal?

Rare1

Normal. You kept your foot in it but it didn't want to shift at 2100 RPM. Had you gone faster or lifted your foot it would have shifted up. You don't want it in third at 1500 RPM, 30 MPH, trying to accellerate up a hill, do you? Shudder, shudder, shudder

chop342

I would agree with Rare1 on that you just had enough engine load and lack of vehicle speed that your govenor pressure had not over come your throttle pressure and therefore i wouldn't upshift. I would say normal.

TIMMY22

ok, I guess there is no lockup in 2nd with the 47re? It's tough to tell if it's locked with no load on it. So, I'm best off to just keep it under I think 37mph so she doesn't get the signal from the wheel speed sensor to shift into 3rd?

macano

I had a similar learning experiance this last weekend. We just finished some work in CA south of Las Vegas and I had to get the loaded trailer out of there and home to Idaho. Well, for those that know I-15 the hill out of Baker, CA to Las Vegas is doosy. My truck would shift to third but not lock up and I'd build some fairly high temps (coolant, tranny, and egt) but, when I finally just put the ol girl into 2nd all my temps went down and I really only lost about 5 mph at 2000 to 2100 or so. I pull shizza all the time and usually don't have any issues but this hill and that load (just like above I am sure it was way way overloaded) I did run into that same things.

So to echo - sounds normal now that I know what I learned this last weekend.

ckt_santiago

The stock valve body doesn't have the provisions to lock up in 2nd or first, however 3rd and reverse do have lockup (reverse would only work if you manually control your lockup). I can get a Transgo shift improver kit to bring up your line pressures to a variable 90-140psi (vs 50-90psi stock) and modify your valve body for lock up in your choice of all three gears or 2nd and 3rd. The shift improver kit is $60 and can usually be installed by the average Joe. PM me if you would like help/parts.

That load shouldn't have been too heavy for your truck though... So long as you don't plan on making that trip or trips like it regularly with a similar load. If you plan on towing at all I would HIGHLY suggest aforementioned shift kit and a billet triple lock TC. I am actually personally going to be freshening my tranny up this weekend so that I can tow heavy. I went with the Transgo SK, Borg-warner frictions and steelies, and a Goerend lifetime warranty triple lock. The set up is figured to hold 800+ hp or 27k CGVW should I decide to go billet everything.