Towing and transmission issue

[Jackpine]

RGSMDNR, I'm going to move this thread into the Towing forum when I finish this reply.

Tell me though, what rear end do you have on your truck? And, is it equipped with the factory tow package? I'm guessing you have 3.73 gears with the tow package, but I just wanted confirmation.

Now, as you probably know, I tow too, not as much weight as you (about 3600# in the trailer) but by the time we factor in all the other crap that's in the bed plus the bed cap, I'm easily pulling 4000#. I've pulled this all over the Colorado Rockies and over some passes above 11,000 ft and up grades over 7% for 7-10 mile distances. I almost always have to do this pulling in 2nd gear, and the transmission fluid will get up to abut 220F. I can maintain 60-65 mph doing this, but my engine is screaming at 4000 rpm.

There's no way I can do this in 3rd gear. It simply does not have the power in that gear range. I have to be in 2nd. If the transmission doesn't "hunt" between 2nd and 3rd, I'll usually leave it in Drive (with the overdrive turned off). If there's any tendency to shift up and down though, I lock it in 2nd.

I find as soon as the rpms increase above 2500, the TFT starts going up. If you set the shifter in 2nd, there is a power reduction (probably for slippery starts) that is applied until you reach a certain speed. This was discussed in another thread quite a while ago. Supposedly, this reduction is not applied as long as the shifter is in Drive.

The towing tunes are designed to give you more low end torque and are not really designed for high speed torque. Since I try not to exceed 65 mph (about 108 kph, I think), this is not much of a factor for me.

I have not noticed any power reduction caused by high fluid temperatures though.

I try to not let the speed fall off in a hill climb, so I don't have to make it back up, and I've never seen the transmission drop into 1st. I monitor "Comm Gear" when towing and the torque converter is usually always locked up under these conditions too.

It's possible you MAY be expecting too much out of a 150? And, you may have a much higher "combined weight" than you realize. I know I did. When I weighed my truck trailer combination on a scale, I found I was about 60# over the weight limit for the rear axle. I've since made an adjustment to the equalizing hitch to correct this.

Somebody else recently said somewhere that about the most you can "comfortably tow" with a 150 is about 5000#. I know there are people who tow more, and I know having higher rear end gearing will help with that too.

I can't give you any more to address your concern than this. And again, I've never seen the pulling power drop off with higher TFTs.

- Jack

[88Racing]

Here's a thread with some good info for everyone.

http://dygytalworld.ehost-services13...ht=temperature

Jack has posted some good numbers in it.

Lars

[RGSMDNR]

Yes im sure I have the 3.73s. Next time I tow Ill hit a scale and see what the actual weight is. Maybe I am expecting too much but even on level ground I find the truck slowing down and am having to step on it (to shift it in 2nd) to get back up to speed.

[TXWolf]

RGSMDNR, I recently bought a 36' travel trailer. When it's loaded with everything we just HAVE to have for camping,, I'm sure the weight is around 8000 lbs. We just came back from a trip to the Texas Hill Country, and I am SO impressed with the pulling power of my 2008 F150. I was able to maintaing 55-65mph very easily. Now, when I hit a long, gradual uphill grade .... I'd have to mash the pedal, the rpm's would jump up to 4000-4200, but I never felt like the truck COULDN'T handle the weight.

I know that my TFT has been around the 230 degree mark area a couple of times, so I'm going to flush the fluid and go with full synthetic. But even with the TFT up quite a bit more than yours is indicating, I still had plenty of pulling power.

Just my

[Longshot270]

I'm guessing that you have the 5.4 right? Many of the power curves I've seen show that the engine's peak torque is somewhere around 3000, after that it starts dropping off(slowly though). And yes I admit I could be a little off on this.

Also do you pull with O/D off? Some people say to not tow in O/D but my dad and many others around here have always used it and wont be convinced otherwise. My dad's truck has over 150K and he has had trouble one time but thats because he forgot he had a heavy trailer hooked up and punched it at a light. All that did was throw a code, after clearing that at a local shop it hasn't had any issues what so ever. And that is the only time that truck has ever been at an auto shop.

Another thing, all of the hot rodding auto guys I know swear by Royal purple and their trucks and tranny's have been pushed extremely hard and are still going.

just my $.02

PS: txwolf, how'd ya like pedernales falls state park?
Haha, Txwolf ignore this, didn't see you had a separate post.

[RGSMDNR]

I usually have OD off while towing unless im heading down a hill or something (being in 3rd seems to slow the truck down). I cant see how your truck can pull that 36' trailer, have the TFT hit 200+ and still maintain a good speed. My truck just cant seem to do that.

[Jackpine]

I wonder if your transmission is "slipping" under load and with the fluid hot? Is it still under warranty? If so, set it back to stock, remove the Gryphon and take it to your dealer. I think they may need to "look" at it.

I think I'd do this even if the truck is out of warranty.

This doesn't sound like something I'd like to see continue, because it could be an early sign of damage.

You should NOT be having problems pulling a 5000# load. You'll certainly know it's there, but the truck was designed to do this task.

- Jack