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Catch14me · 10-01-2012, 05:34 PM

I am towing a Jeep Grand Cherokee behind my 2006 Winnabego 350 HP Journey with the Allison 3000 6 speed trans. Previous toads were lighter and I was wondering if leaving in 6th gear was appropriate considering the weight of the Jeep while towing on typical primary and interstate roads. I know if the transmission is downshifting a lot or if on steep grades a lower gear should be selected but a little concerned about the trans temp since it has no gauge to tell me the temp. I also watch the engine rpms.

jlfbatonrg · 10-01-2012, 06:18 PM

I would think you're OK in 6th gear. We tow a ~3500 Saturn Vue with our Expedition 38N, and Cummins 300hp and have no problems. I purchased a ScanGaugeD system to monitor turbo boost pressure and transmission temperature along with some other parameters, and our transmission temp doesn't go above 190F. That temp was reachd while climbing Black Mountian pass in NC. It's a 6% grade and six miles long. for that climb the tranny dropped down to 5th gear. On normal running the temps ranger from 165-185F.

rgvtexan · 10-01-2012, 10:13 PM

I have the 350 cummins and tow a Honda Odyssey ~5000 lbs loaded. I watch the engine with a Silverleif VMSpc and I have never run hot. Sixth gear is fine, that Allison knows when to shift.

Mr_D · 10-01-2012, 10:29 PM

Quote:

Originally Posted by rgvtexan

I have the 350 cummins and tow a Honda Odyssey ~5000 lbs loaded. I watch the engine with a Silverleif VMSpc and I have never run hot. Sixth gear is fine, that Allison knows when to shift.

Pretty much the same here although we have a Banks kit and the torque/hp band is much wider than stock, plus our Ody is on a dolly so that adds about 650#'s to the weight.

Catch14me · 10-02-2012, 04:35 AM

Thanks for the reassurance. My previous RV had gauges for both turbo boost and trans temp that I could monitor but I also towed lighter vehicles. We will be traveling to Gatlinburg TN next week and may go the Ashville route from Richmond VA area rather than I64/I81.

Catch14me · 10-02-2012, 11:11 AM

Quote:

Originally Posted by jlfbatonrg

I would think you're OK in 6th gear. We tow a ~3500 Saturn Vue with our Expedition 38N, and Cummins 300hp and have no problems. I purchased a ScanGaugeD system to monitor turbo boost pressure and transmission temperature along with some other parameters, and our transmission temp doesn't go above 190F. That temp was reachd while climbing Black Mountian pass in NC. It's a 6% grade and six miles long. for that climb the tranny dropped down to 5th gear. On normal running the temps ranger from 165-185F.

Just checked out the Black Mountain Pass. Did you by chance go on route 441 from Cherokee to Gatlinburg? Think I may pass on that route and go I81 to I40 and Route 321. I believe she can make it but wife may not like. Thanks.

jlfbatonrg · 10-02-2012, 01:38 PM

No we drove I-40 from Knoxville,TN to Marion, NC (going East the grade is not bad at all going up Black Mountain pass (hardly came out of 6 gear except for the 50 mph speed limit in a few places. When we came back, we drove from Marion,NC to Sevierville,TN on I-40, got off Exit 407 and drove Rt 66 to the River Plantation RV Resort. We went to Gatlinburg, etc. in the Vue. I think, if you come down I-81 you won't go over Black Mountain Pass to get to Gatlinburg.

RickO · 10-02-2012, 02:05 PM

We towed a Jeep GC for a couple of years behind our 07 Winnie... but I have the 400ISL. Never a problem. We now tow an Explorer and still hardly know it's back there at all. I monitor with a VMSPc.

If you're getting a lot of downshifting on rolling hills, etc... you might try using the "econ" mode on the Allison which should delay the shift points a bit.

That tranny and engine combo is really pretty smart and they work together well, so I wouldn't be too concerned about doing harm by just towing. Do watch your engine temps when making long hard climbs in hot weather and downshift to keep the RPM up and the temps from getting too high.

Good luck.

Rick

Catch14me · 10-02-2012, 03:05 PM

Quote:

Originally Posted by jlfbatonrg

No we drove I-40 from Knoxville,TN to Marion, NC (going East the grade is not bad at all going up Black Mountain pass (hardly came out of 6 gear except for the 50 mph speed limit in a few places. When we came back, we drove from Marion,NC to Sevierville,TN on I-40, got off Exit 407 and drove Rt 66 to the River Plantation RV Resort. We went to Gatlinburg, etc. in the Vue. I think, if you come down I-81 you won't go over Black Mountain Pass to get to Gatlinburg.

Thanks, I started the thread to see what experience other RVs had towing a relatively heavy toad with their Allison and the gear used but since we are traveling to nearly the same place as you did I40 might be an alternative to I81 and a chance to visit the Ashville area. Good Sam Trip Planner had us go on Route 441 on the last leg to Gatlinburg with the criteria I plugged in (no low bridges and favor interstate) which I know is a very steep and curvy road. How is I40 through the Cherokee National Forest?

jlfbatonrg · 10-02-2012, 03:44 PM

Evans,

I-40 through the Cherokee National Forest from Asheville going West isn't bad at all. It's hilly and curvy, but really not a problem. We traversed it in both directions and had no issues whatsoever. There are 2 small tunnels on the route, and the road is very well marked so you know when a curve is coming and what the required speed is. It is also scenic. I don't remember passing any 18 wheelers in that stretch and we ran the posted speed limits throughout.

Lynda looked at the map and thought you could come down I-85 to I-40 then go west toward Knoxville,TN. We exited at exit 407, Rt66 (Sevierville, TN) and went to the RV resort from there.

Catch14me · 10-02-2012, 04:00 PM

Quote:

Originally Posted by jlfbatonrg

Evans,

I-40 through the Cherokee National Forest from Asheville going West isn't bad at all. It's hilly and curvy, but really not a problem. We traversed it in both directions and had no issues whatsoever. There are 2 small tunnels on the route, and the road is very well marked so you know when a curve is coming and what the required speed is. It is also scenic. I don't remember passing any 18 wheelers in that stretch and we ran the posted speed limits throughout.

Lynda looked at the map and thought you could come down I-85 to I-40 then go west toward Knoxville,TN. We exited at exit 407, Rt66 (Sevierville, TN) and went to the RV resort from there.

Sorry to keep bugging you but do you recall the height of the tunnels on I40 in the Cherokee National Forest. I know the Blue Ridge Parkway and Skyline Drive in VA have a couple too small for comfort.

jlfbatonrg · 10-02-2012, 04:04 PM

Evans,

I don't remember the heights, but they are no problem for 18 wheelers or RVs like ours, we cleared them and it wasn't close.

You're no bugging me. This forum is to share information. I'm sure you'd do the same if we needed info you had.

jlfbatonrg · 10-02-2012, 04:16 PM

Evans,

Just dawned on me. Have you driven in the mountains before? I have found that driving our coach at about 80-85% throttle seems to be the most effective for keeping the rpms around 1900-2000 and the tranny staying in its selected gear. I have also learned that on our coach, running in Economy mode instead of Perfomance mode keeps the trany from searching between gears.driving like this doesn't overheat the engine or tranny on our coach.

Catch14me · 10-02-2012, 06:14 PM

Quote:

Originally Posted by jlfbatonrg

Evans,

Just dawned on me. Have you driven in the mountains before? I have found that driving our coach at about 80-85% throttle seems to be the most effective for keeping the rpms around 1900-2000 and the tranny staying in its selected gear. I have also learned that on our coach, running in Economy mode instead of Perfomance mode keeps the trany from searching between gears.driving like this doesn't overheat the engine or tranny on our coach.

Thanks, I have had experience with the mountains in Virginia and except for being a little slow on the very steep grades haven't had any problems with my previous toads and a slightly higher torque engine. The exhaust brake and new brake buddy help a lot on the descent but I will give the econ mode a try on the climbs. As suggested I downshift to keep the rpms around 2000 on the climb if the trans wants to shift a lot on it's own. I have had brakes over heat on the Blue Ridge Parkway but not in a diesel with exhaust brake. Lost a transmission one time pulling a trailer with a diesel chevy suburban.