Towing Questions

[F-125Racer]

I'm a noob here, trying to learn about my taco, but I've lurked for a few months. Great group here, super informative.
I am towing a single-axle, 6' x 6' x 12' long, V-nose Featherlite enclosed trailer with a total weight of 4,400lbs, with about 500lbs on the front. Friction-type sway control is installed. I just finished my first trip and I've got a few questions I didn't find when searching:
1) The truck handled the weight fine, power was ok. Shifting didn't seem right. On cruise, the tranny would downshift on small grades. When I drove without cruise, I could easily hold speed with minimal accelerator pedal movement without the tranny downshifting. By driving like this, I could go a long way with some sizeable grades maintaining 75 mph and the tranny would never have to downshift. Then I'd punch in the cruise and I would get one, and sometimes two downshifts on similar grades, then it would "hang" at high rpms for quite a ways past the crest of the hill, at the pre-set speed. I ended up not using cruise at all. Is there any fix for this ?
2) Anybody towing with a supercharger ? Did the re-flash help the shifting, or did the additional power just let the truck stay in higher gears ? I got about 10mpg on the trip, would the S/C make this better, worse, same???
3) Are there any published dyno charts showing stock HP and Torque, vs supercharged HP and Torque across the rpm range ?
4) Any other reco's for more towing power, better mileage, better shifting?

[MAXTacoma]

Originally Posted by F-125Racer

I'm a noob here, trying to learn about my taco, but I've lurked for a few months. Great group here, super informative.
I am towing a single-axle, 6' x 6' x 12' long, V-nose Featherlite enclosed trailer with a total weight of 4,400lbs, with about 500lbs on the front. Friction-type sway control is installed. I just finished my first trip and I've got a few questions I didn't find when searching:
1) The truck handled the weight fine, power was ok. Shifting didn't seem right. On cruise, the tranny would downshift on small grades. When I drove without cruise, I could easily hold speed with minimal accelerator pedal movement without the tranny downshifting. By driving like this, I could go a long way with some sizeable grades maintaining 75 mph and the tranny would never have to downshift. Then I'd punch in the cruise and I would get one, and sometimes two downshifts on similar grades, then it would "hang" at high rpms for quite a ways past the crest of the hill, at the pre-set speed. I ended up not using cruise at all. Is there any fix for this ?
2) Anybody towing with a supercharger ? Did the re-flash help the shifting, or did the additional power just let the truck stay in higher gears ? I got about 10mpg on the trip, would the S/C make this better, worse, same???
3) Are there any published dyno charts showing stock HP and Torque, vs supercharged HP and Torque across the rpm range ?
4) Any other reco's for more towing power, better mileage, better shifting?

Towed a Porsche from Cincinnati down to Atlanta on a flat bed trailer. Mine did the same thing. I never use cruise when I tow. It always seem to give it way to much gas on small hills and then its hunting for gears the whole time. Towing my boat (2800 LBS) I'm usually at 12-14 mpg..

[OffroadToy]

I would recommend not useing your cruise control while towing. Downshift to 4th gear if your transmission is hunting for a more suitable gear while going up hills, and downshift to 4th while going down hills to take advantage of engine braking. If the transmission is constantly searching for a gear you'll take a chance of overheating or damaging your transmission...especially since the sport models don't have the transmission coolers.

[MAXTacoma]

Originally Posted by OffroadToy

I would recommend not useing your cruise control while towing. Downshift to 4th gear if your transmission is hunting for a more suitable gear while going up hills, and downshift to 4th while going down hills to take advantage of engine braking. If the transmission is constantly searching for a gear you'll take a chance of overheating or damaging your transmission...especially since the sport models don't have the transmission coolers.

Sports dont have trans. coolers???? I thought that the tow package gave you a trans cooler?

[OffroadToy]

Originally Posted by MAXTacoma

Sports dont have trans. coolers???? I thought that the tow package gave you a trans cooler?

I stand corrected. For some reason I was thinking it was part of the Offroad Package.

[NraFan]

Cruise control does this to me a lot on grades even while im not towing. I dont think it was the towing giving you hassle.

[MAXTacoma]

Originally Posted by OffroadToy

I stand corrected. For some reason I was thinking it was part of the Offroad Package.

Ok that made me a little nervouse, I tow a lot so having the cooler is very important.

[MMOCGuy]

It could be happening because the cruise control operates by "Sensing" the amount of drag in the engine when climbing a hill and responds accordingly. This is a bit of a simplified explanation but it might help. When you have extra weight on the back as in towing a trailer, the criuse control thinks there is more engine lugging going on that actually is so it wants to downshift sooner and more often than if the extra weight wasn't there.

Personally, I never use cruise control when pulling a trailer. I want to control the transmission and throttle myself in case I have to take evasive action or slow suddenly. Another reason I don't like to use cruise control is that it uses the truck brakes to maintain the speed when going downhill. I'm not sure if it applies the trailer brakes also and if it doesn't, it makes it hard on the truck front disks trying to hold back all of that extra weight.

I hope this helps.

Norm.

[RelentlessTaco]

you can find some dyno graphs HERE

[F-125Racer]

Ever seen a chart just like that for the TRD supercharger ?