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Discussion Starter · #1 ·
I have a 2002 Trooper very well maintained with low mileage. I recently purchased a 3000lb RV and towed it about 300 miles. Although the tow rating is 5000lbs I found that the trooper struggled with the load. I ran in 3rd gear as it was difficult to maintan crusing speed (60-65) without the trans continually downshifting. At about 60mph in 3rd I am turning about 3000rpm which I know happens to be at peak tourqe rating (215foot lbs). I would prefer not to spin the motor that fast for an extended period of time but now have no other choice. I have 245/75 16 tires and was woundering if I might put 15in wheels and say 225/70 15s on to effectively raise the gear ratio. Does anybody know if that would change much. I want to be able to stay in 4th most of the time. Any other ideas would be appreciated.
 

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I am baffled by your complaint. Not trying to insult you, just confused. I have the same Trooper with 265/75R16 tires which effectively lowers my gear ratio in effect hurting my towing ability.

I regularly tow my 3500-4000lbs popup camper or my 2500lbs boat down the highway at 65-75mph with no trouble. YES, towing will put added strain on the truck. You will see a noticable drop in fuel milage. I usually get around 9-10mpg while towing vs. 15-16mpg without the trailer. Then again I have a lead foot.

If you haven't already I will make these suggestions. Add an auxilary transmission cooler ASAP. Some member have also added an extra transmission fluid spin on filter and transmission temp gauges can be handy too. When towing always use the "power" setting for the transmission. This raises the shift points and also raises the transmission line preasure. This will help limit the transmission slipping and by doing this help keep the transmission cooler and therefore limiting damage.

The only question I didn't ask is what type of camper you are towing. If it is a conventional travel trailer then you have a lot of surface area you are trying to drag through the air. Just be patient and know that you are not going to pull hills like a V8. I usually pull mountain grades around 45-55mph with my hazzards on. By only running high RPMs for a short time as long as you have oil you aren't doing any damage other than burning through some fuel.

Good Luck and feel free to post up any questions. This is a very knowledgeable group and we don't bite... Most of the time. :lol:
 

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Discussion Starter · #3 ·
Thanks for your reply. I do have a tranny cooler and I even had a fluid change as I know I would towing. I am interested in the spin on idea if you could give me a little more info on that. Finally, I allways leave the "power" button on but do you tow in 3rd or leave it in high and allow it to downshift when it wants to. Thanks again
 

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damn.. without a trailer im doing 60 at 3k in 5th! i wish i had an auto sometimes
 

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2002trooper4me said:
When you switch on the power mode a couple of things happen.
1. The transmission line pressure is increased resulting in firmer shifts.
2. The transmission RPM shift points are increased to keep the engine in the higher RPM power band.

These things will result in more "getty-up", more fuel consumption.

I normally leave it turned off in my Trooper unless I am towing or wheeling. The increased line pressure will help keep the tranny from slipping which will increase its life expectancy in these trucks when we start leaning on the skinny pedal.

The winter switch does a few different things.
1. The truck will start off the line in second gear instead of first.
2. The line pressure will drop allowing the tranny to slip a little cushioning the driveline to help prevent spinning the tires.
3. The Transmission RPM shift points are lowered to effectively "de-power" the engine by taking it out of it's natural power band.

Good Luck!!
part of what power mode does it make your shift points later, it makes the transmission try to stay in the power band right around 3000. maybe if you get up to speed and then turn power mode off it might lower the rpms.
 

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THe max torque is rated at around 3k so it does make sense.
 

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2002trooper4me said:
I am baffled by your complaint. Not trying to insult you, just confused. I have the same Trooper with 265/75R16 tires which effectively lowers my gear ratio in effect hurting my towing ability.

I regularly tow my 3500-4000lbs popup camper or my 2500lbs boat down the highway at 65-75mph with no trouble. YES, towing will put added strain on the truck. You will see a noticable drop in fuel milage. I usually get around 9-10mpg while towing vs. 15-16mpg without the trailer. Then again I have a lead foot.

If you haven't already I will make these suggestions. Add an auxilary transmission cooler ASAP. Some member have also added an extra transmission fluid spin on filter and transmission temp gauges can be handy too. When towing always use the "power" setting for the transmission. This raises the shift points and also raises the transmission line preasure. This will help limit the transmission slipping and by doing this help keep the transmission cooler and therefore limiting damage.

The only question I didn't ask is what type of camper you are towing. If it is a conventional travel trailer then you have a lot of surface area you are trying to drag through the air. Just be patient and know that you are not going to pull hills like a V8. I usually pull mountain grades around 45-55mph with my hazzards on. By only running high RPMs for a short time as long as you have oil you aren't doing any damage other than burning through some fuel.

Good Luck and feel free to post up any questions. This is a very knowledgeable group and we don't bite... Most of the time. :lol:
HEY MIKE , I DONT SEEM TO HAVE ANY POWER PROB TOWING MY TRAILER AND IT WEIGHS IN AT 3500 LB AND I HAVE 245 X75 16 TIRES , SEEMS TO HAVE PLENTY OF POWER , DONT YOU THINK
 

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JLEMOND said:
2002trooper4me said:
I am baffled by your complaint. Not trying to insult you, just confused. I have the same Trooper with 265/75R16 tires which effectively lowers my gear ratio in effect hurting my towing ability.

I regularly tow my 3500-4000lbs popup camper or my 2500lbs boat down the highway at 65-75mph with no trouble. YES, towing will put added strain on the truck. You will see a noticable drop in fuel milage. I usually get around 9-10mpg while towing vs. 15-16mpg without the trailer. Then again I have a lead foot.

If you haven't already I will make these suggestions. Add an auxilary transmission cooler ASAP. Some member have also added an extra transmission fluid spin on filter and transmission temp gauges can be handy too. When towing always use the "power" setting for the transmission. This raises the shift points and also raises the transmission line preasure. This will help limit the transmission slipping and by doing this help keep the transmission cooler and therefore limiting damage.

The only question I didn't ask is what type of camper you are towing. If it is a conventional travel trailer then you have a lot of surface area you are trying to drag through the air. Just be patient and know that you are not going to pull hills like a V8. I usually pull mountain grades around 45-55mph with my hazzards on. By only running high RPMs for a short time as long as you have oil you aren't doing any damage other than burning through some fuel.

Good Luck and feel free to post up any questions. This is a very knowledgeable group and we don't bite... Most of the time. :lol:
HEY MIKE , I DONT SEEM TO HAVE ANY POWER PROB TOWING MY TRAILER AND IT WEIGHS IN AT 3500 LB AND I HAVE 245 X75 16 TIRES , SEEMS TO HAVE PLENTY OF POWER , DONT YOU THINK
I think that has something to do with that air compressor hooked up to your intake manifold!
 

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walloon said:
I have a 2002 Trooper very well maintained with low mileage. I recently purchased a 3000lb RV and towed it about 300 miles. Although the tow rating is 5000lbs I found that the trooper struggled with the load. I ran in 3rd gear as it was difficult to maintan crusing speed (60-65) without the trans continually downshifting. At about 60mph in 3rd I am turning about 3000rpm which I know happens to be at peak tourqe rating (215foot lbs). I would prefer not to spin the motor that fast for an extended period of time but now have no other choice. I have 245/75 16 tires and was woundering if I might put 15in wheels and say 225/70 15s on to effectively raise the gear ratio. Does anybody know if that would change much. I want to be able to stay in 4th most of the time. Any other ideas would be appreciated.
I towed over 2000lbs of trailer about 2700 miles with a Ford Focus,with a 1.8L 4 cylinder and a rated towing capacity of about 1000Lbs. It pulled it off without a single hiccup. I think you guys are spoiled.
 

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squatch said:
JLEMOND said:
2002trooper4me said:
I am baffled by your complaint. Not trying to insult you, just confused. I have the same Trooper with 265/75R16 tires which effectively lowers my gear ratio in effect hurting my towing ability.

I regularly tow my 3500-4000lbs popup camper or my 2500lbs boat down the highway at 65-75mph with no trouble. YES, towing will put added strain on the truck. You will see a noticable drop in fuel milage. I usually get around 9-10mpg while towing vs. 15-16mpg without the trailer. Then again I have a lead foot.

If you haven't already I will make these suggestions. Add an auxilary transmission cooler ASAP. Some member have also added an extra transmission fluid spin on filter and transmission temp gauges can be handy too. When towing always use the "power" setting for the transmission. This raises the shift points and also raises the transmission line preasure. This will help limit the transmission slipping and by doing this help keep the transmission cooler and therefore limiting damage.

The only question I didn't ask is what type of camper you are towing. If it is a conventional travel trailer then you have a lot of surface area you are trying to drag through the air. Just be patient and know that you are not going to pull hills like a V8. I usually pull mountain grades around 45-55mph with my hazzards on. By only running high RPMs for a short time as long as you have oil you aren't doing any damage other than burning through some fuel.

Good Luck and feel free to post up any questions. This is a very knowledgeable group and we don't bite... Most of the time. :lol:
HEY MIKE , I DONT SEEM TO HAVE ANY POWER PROB TOWING MY TRAILER AND IT WEIGHS IN AT 3500 LB AND I HAVE 245 X75 16 TIRES , SEEMS TO HAVE PLENTY OF POWER , DONT YOU THINK
I think that has something to do with that air compressor hooked up to your intake manifold!
THAT MAY BE THE CASE , NOW IF I COULD SLOW DOWN THAT BIG GAS LEAK, THOSE 6 SMALL ONES SEEM TO BE THE MAIN PROBLEM
 

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Tow in top gear like you would driving without a load. If the torque converter unlocks and you can tell it will be un locked for some time due to the terrain then down shift. Try and keep it so the torque converter remains locked. This will reduce heat input to the oil significantly. Also if you find you going up a hill and the transmission cannot make up it mind on which gear to be in then drop it to the lower gear and back off the throttle a bit and take your time up the hill.

On reason I prefer a manual over an auto is I can select the gear I need for a hill and just stand on the gas :) I am about to haul a couple thousand pounds up our notorious British Columbia mountain hills this weekend. Should be fun!
 

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walloon said:
Thanks for your reply. I do have a tranny cooler and I even had a fluid change as I know I would towing. I am interested in the spin on idea if you could give me a little more info on that. Finally, I allways leave the "power" button on but do you tow in 3rd or leave it in high and allow it to downshift when it wants to. Thanks again
JJLEMOND who posted also has the spin-on filter setup that I was referring to. He is a wealth of knowledge and I will volunteer his service for this effort. Feel free to PM him. He was kidding me about towing with his Trooper for he has a very rare Supercharged Trooper. That thing is ridiculous how much power it makes.

Also leave the trans in Drive unless you are pulling a steep grade or descending one. The thing you need to do is to pay attention to the coolant temp and how the truck is doing. If needed drop a gear and slow down. There are many schools of thought on this but on long grades the best plan is to find a gear that you can still accelerate in and hold a comfortable RPM. This will ensure that you aren't overworking the engine since you still have power left in reserve. This also means that you are not at wide open throttle so you are maximizing your possible fuel mileage.

This is one of the techniques that we use in Trucking to maximize fuel mileage in the mountains. Fuel is one of the highest operating expenses so it is monitored closely.

Good luck!
 
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