Towing steep grades in the AZ heat: opinions needed

[Rancho5]

My Popup, a 2000 Coleman Cheyenne, dry weight 1969 lbs, is at my in-laws in Mesa, AZ. We are going down from Albuquerque this weekend to pick it up before it gets too hot.

I’ve never towed my Popup with my 2002 Sport before (used to have a f250 with w 7.3) but as soon as I bought it I installed a new radiator and a large tranny cooler installed in line with the new radiator. Then I installed EngineLink to monitor tranny temps.

Weather in Mesa is supposed to be a high of 93 this weekend. We are planning on leaving Mesa after dark and go to Payson and stay overnight. Then to Heber, hit the I-40 and go home.

The incline from Mesa to Heber is pretty severe, especially the Mogollon Rim.

I’ll keep the rig out of overdrive the entire trip, flat or not.

For those experienced AZ towers, think I’ll be OK? Just a little nervous because with my 7.3 I pulled that camper anywhere, anytime and up any incline.

 

[LittleCaesar]

Try and tow out of OD. Not always easy at highway speeds. AC off if you can stand it.

Make sure all fluids are good along with brakes and a working fan clutch.

I'd really make sure to have an external tranny cooler, along with a 3 core Champion radiator, for maximum cooling. Tundra brakes would help.

Why did you get rid of the 7.3?

 

[Rancho5]

Try and tow out of OD. Not always easy at highway speeds. AC off if you can stand it.

Make sure all fluids are good along with brakes and a working fan clutch.

I'd really make sure to have an external tranny cooler, along with a 3 core Champion radiator, for maximum cooling. Tundra brakes would help.

Why did you get rid of the 7.3?

Yep, I'll be towing out of OD, A/C off. External tranny cooler installed in line with new radiator, not champion.

I traded the 7.3 for the T4R. The 7.3 had 300k on it, and I know it would have gone longer. The kids are grown and gone though, and there is no need for a beast truck anymore. Plus, it was getting tired, or I was...and my wife hated driving it because she's small. So I traded it for an 02 Sport with 150k.

 

[LittleCaesar]

My uncle had one on his farm in Delaware, believing it had about 600k on it when the second transmission went. Sold it to his head ranch hand for $500. Guy put in another tranny and is still driving it today, approaching 700k. Tough engine.

Good luck with the tow.

 

[thegipper]

The 7.3 was a good engine for sure.

 

[Rimcrew]

You'll be fine. It's not going to be that hot, and the pull up the rim is not really that bad, and it's not very long.

 

[Rancho5]

You'll be fine. It's not going to be that hot, and the pull up the rim is not really that bad, and it's not very long.

And from your name I’m assuming you know the area quite well Thanks.

 

[phattyduck]

You are towing around half the rated weight. 93*F is not hot. Enjoy your AC. 60mph in 3rd should be around 2600rpm, which is pretty comfortable for the engine and passengers. Not even sure why you are worried...

-Charlie

 

[2018SilverRunner]

why not just take the 17 up to Flagstaff then jump on the 40? Might save you some time compared to going all the way up the rim to Heber then over. Not sure though never been that way.

 

[bwarren]

I've towed over 2000lbs with a fully loaded 1996 2.7 3rz-fe in mid-summer all over the mountain west. You'll be more than fine with the 3.4. Just turn off the OD when going up steep hills, this is must with my 4 cylinder. Like others have said, make sure your radiator and brakes are in good shape.

 

[Rancho5]

You are towing around half the rated weight. 93*F is not hot. Enjoy your AC. 60mph in 3rd should be around 2600rpm, which is pretty comfortable for the engine and passengers. Not even sure why you are worried...

-Charlie

just the first time towing with this rig, and coming from a Powerstroke background where I could tow anything. With the PS I didn’t have to install a tranny cooler, didn’t have to take it out of OD, etc, so I’m just being cautious on my first tow. Thanks for the help

 

[Rancho5]

why not just take the 17 up to Flagstaff then jump on the 40? Might save you some time compared to going all the way up the rim to Heber then over. Not sure though never been that way.

A bit quicker through Heber, and my mom lives in Payson...Mother’s Day!

 

[mtbtim]

The important thing is you're monitoring your trans temps. On slow mountain road climbs, tranny temps do begin to soar. There's a 7 mile climb near me in the Santa Cruz mountains that gains around 2000 feet of elevation. If I can keep my speed up and get into 3rd gear with OD off, I can keep my trans temps well below 200. If I'm following slower drivers and can't maintain 3rd gear, my trans temps will be over 200 by the top of the hill. Before I had an external cooler ran in-series with my radiator cooler, I could hit 220-230 no problem. Now with the external trans cooler, I usually hit no higher than the low 200's.

For me, 230 F is the point I start thinking of pulling over and giving my transmission a rest because the trans fluid life starts to drop off dramatically above the 230 mark.

I did a recent mellow wheeling trip with [MENTION=148218]JZiggy[/MENTION] above Hwy 1 near Big Sur and I learned an important lesson on 4WD gearing and auto trans temps. We started climbing some steep sustained fire roads and I was in 2Hi. I quickly noticed my trans temps were going through the roof so I kept stopping to give my transmission a break. Jordan asked me if I was in 4lo and I told him no. I tried 4lo and it made a huge difference. That was a big learning experience for me. I have more experience 4wheeling with a manual transmission than an automatic and had no clue that the transfer case gearing would have such an effect on the trans temps. In 4hi, I was getting well above 200 F. When I switched to 4lo, my trans temps never rose above 170 F. In the past, I used 4lo for super steep trails mainly to control my speed downhill so I wouldn't have to ride the brakes. But now, I'm going to be using 4lo a lot more just for load it takes off my transmission.

 

[jgue467]

...
But now, I'm going to be using 4lo a lot more just for load it takes off my transmission.

And to add to this, if it's desired to travel in 4Lo at around say 10-15mph, start in 2nd (auto selector) and the trans won't do the 1-2 "punch" shift.

Those who've used 4Lo know what i mean. :cowboy:

 

[LittleCaesar]

just the first time towing with this rig, and coming from a Powerstroke background where I could tow anything. With the PS I didn’t have to install a tranny cooler, didn’t have to take it out of OD, etc, so I’m just being cautious on my first tow. Thanks for the help

I didn't mean to sound overtly cautious, but towing with a 4runner vs F350 in any capacity is a night and day difference. But you should be fine.

 

[gamefreakgc]

I've towed over 2000lbs with a fully loaded 1996 2.7 3rz-fe in mid-summer all over the mountain west. You'll be more than fine with the 3.4. Just turn off the OD when going up steep hills, this is must with my 4 cylinder. Like others have said, make sure your radiator and brakes are in good shape.

Agree with this sentiment. Last time I towed I had about ~1600 lbs behind me and I hardly noticed it except for when braking. To be honest, brakes are the weak point here for towing, not the transmission.

ECT Power mode helps with towing too if you've got that little button.

 

[Rancho5]

...towing with a 4runner vs F350 in any capacity is a night and day difference.

Hence, my cautious attitude Thanks for the reassurance.

 

[Rancho5]

My VSC TRAC light is on, as well as the VSC OFF and Check Engine light. Will I still be alright towing my popup?

I've changed the gas cap and that made no difference. I will not have time to troubleshoot until after the tow. I'm thinking since the codes thrown are emission codes I'm good.

Thoughts?

 

[phattyduck]

Assuming its either p0420 or p0440 you are fine towing.

VSC/TRAC and CEL together can also mean issues with the brake booster/ABS/traction control unit, so make sure it isn't that.

-Charlie

 

[Rancho5]

Assuming its either p0420 or p0440 you are fine towing.

VSC/TRAC and CEL together can also mean issues with the brake booster/ABS/traction control unit, so make sure it isn't that.

-Charlie

Hopefully it is not. Since I have not had time to diagnose, and we leave tomorrow, what if it is? I just had a new brake controller installed and this will be the first time using it too.

PS. Both those codes were thrown