Towing Less Than 10k with Auto/3.54

[LGarcia]

Hi all, 1st time poster here. I've done a search and read some relevant threads, but am towing my new 5er tomorrow, so I need to make sure I actually understood what I've read.



I have an automatic equipped 2002 SWB SLT+ (I didn't plan on a 5er when I bought it), and just had synthetic put in the differential yesterday, total mileage is 17,500.



I found the lightest 5er I could, a Starcraft Aruba 295 RLS, dry weight is 5750 lbs, so loaded I'm guessing 7-7. 5k, 8k max?



Would I be safe to tow in OD on no headwind flats and downhill with this rig? I understand with OD off, transmission heat build-up is a problem, so should I put it in OD when practical to cool down? With OD off, I'm at 62 mph at 2400 RPM, that will add a lot of time on my 525 mile drive to Reno, and I'm not sure I want to run over 2500 RPM for extended periods, even though I understand that is ok.



Thanks in advance. I've enjoyed my visits to this forum and will post personal info once I figure out how.

 

[Un-Hemi]

Hi. Welcome to the TDR. You are wise to be here.



You will have no problem running as you describe. The heat buildup doesn't come from running with the OD off, but from running with the torque converter lockup clutch disengaged. Third gear-locked up is as good as OD-locked up. As long as the RPM is kept above 1750 RPM in OD under load (some say higher) you will be fine.



I have towed 6000 lbs through the rockies with no trouble; on my truck, when it kicked down out of OD, it would go to 3rd unlocked, and in order to get it locked up again, I had to use the OD off button in the end of the shift lever. I got very proficient at anticipating the downshift to 3rd and would push the button early to get to 3rd locked-up before it was needed. Your truck has a different shifting sequence than mine, so I am hoping that someone with a later truck like yours will chime in with some additional advice.



Good luck; have fun on your trip!

 

[rluft]

My 5th wheel and the truck combined weight is at 18,500. With the power increase I have indicated in my signature I run in OD all the time. I will try to anticipate a downshift to third as in when climbing a hill and will either cancel cruise control so it doesn't down shift or, on long hills, let off the fuel and hit the OD off button so the downshift is not under full power. I think I read somewhere that transmission life is extended if you keep it above 1700 rpm with a load, keeps the line pressure up. So that is what I try to do.



If you don't have a fueling box you probably won't be able to pull as well as I do and the transmission will want to down shift more. The obvious solution to that is to get a fueling box.

 

[Tom G]

Pulling Your 5th Wheel

Hi LGarcia:



Don't worry your truck will do just fine. Last year I took mine over the continental divide which was about 14,000 feet and the truck did just fine. I was pulling my 25 ft. Aljo 5th wheel and used the lower gears when coming down the hills. The transmission NEVER overheated but just in case it got hot I changed the fluid when I got home. Fluid was the original red color and smelled like new stuff so DON'T WORRY.



I tow MOST of the time in O. D. with the torque converter locked up. Run about 65 mph most of the time and get about 11-12 mpg. Truck shifts down frequently in hilly terrain so I usually shut off the cruise control in hilly country.



Do not be afraid to put the pedal to the metal and work the truck. These engines are made to work all day long and mine started running MUCH better after some serious work This year towing should be even more fun since I had a Trans-go shift kit installed. You should put one of these on your Christmas shopping list



Have a safe trip and lots of fun.

 

[GeneralMachine]

Welcome LGarcia

I pull 12k with a boat in tandem and have the same set up as you and have no problem with the trany so far, I don't think you'll have any problem, ditto that after the power enhancement's I also pull in od at all time's it sure made the cummins happy and the driver also. good luck Harv

 

[JBlock]

Your OH in Overdrive

I have towed 3 times from San Francisco to North of Portland Oregon/Washington state through Grants Pass several times at the weight you indicating. I run overdrive everywhere except in the mountain crossing ,Mt. Shasta area, Cal/Oreg. border crossing 20 mile 8% grade, and the Grant Pass pass area, where I run 3rd, and once drop into 2nd.



The last trip I noticed the temperage on the engine going up to 210, I never heard the fan come on. Transmission with the probe in the Double Deep Magtec pan never when off 140 which is the bottom of the scale with a IsoPro Mechaincal I run.



I run 3rd down hill second vvery rarely.



Transmission will heat up fast 220F backing up fully load even in four wheel low, also if you idle in gear for 30 minutes like at the Canadian Border Crossing.



JB