Got hot while towing

GTS · **Posted:** Tue Jun 11, 2013 9:20 pm

So last weekend my girlfriend and I took her T@b to a T@b rally pulling it with her Liberty. Going over Tiger Mt. on the way home I was WOT to maintain speed and did loose a few mph going over the hill but it pulled it OK for the most part. About 3/4 the way up the hill I looked down and saw the engine temps had climbed way up. The temp gauge read at 3/4 or just over and dropped back to normal promptly after cresting the hill and coasting down the other side.

Her T@b weighs about 2,200lbs and is all stock as far as we know. For those of you who town with yours is this normal for them to get hot while pulling a load like this or do I need to start looking into potential issues? I'd like her to get a programmer for it to give it a touch more power for pulling her T@b and a transmission module but I'm kind of worried that trying to get more power out of it will only exacerbate the heating issue. Has anyone had heating issues after adding programmers? Which programmers do you guys recommend other than just the Green Diesel one?

I'm working on getting some gauges in it to measure trans temp, EGT's and boost but being no one seems to make a 3 gauge pod for these I'm going to have to fab something up so needless to say I don't have them in yet.

CATCRD · **Posted:** Tue Jun 11, 2013 9:29 pm

It's not normal, and my first thought is that your fan clutch is dead. Try the Hayden 2905. Yes a power tune will only make things worse until you get that sorted out.
Check out McNally gauges. I have their combo boost/egt and oil temp/pressure in a 2 gauge pod.

flash7210 · **Posted:** Wed Jun 12, 2013 7:23 am

You were at WOT?

What gear were you in?
How fast were you going?
How steep was the grade?

You can maintain 4th gear at 59 mph. That will keep RPM at about 2000 which will keep your
fan speed up and keep your engine at optimal torque.

Pardon my ignorance, but what is a T@b?

papaindigo · **Posted:** Wed Jun 12, 2013 8:13 am

With an 05 the very first thing I'd do is the Hayden fan clutch and the next thing I'd do is at least lock out overdrive when climbing any significant grade pulling a trailer. We did not have any temp problems with a similar load in stoutdog's 06 on I-10 from Tempe, AZ to Tallahassee, FL but then we had no long up grades and were careful to build speed before those grades so as to get over them at decent rpms and no significant loss of speed plus he has the Hayden fan clutch and 11 blade nylon fan.

As to gauges you might look at Glow Shift for a 3 in 1 gauge.

ChooChooman74 · **Posted:** Sat Jun 15, 2013 9:22 am

I tow a travel trailer and have done some experimenting. The engine temperature will start to climb with sustained 1200 to 1300 degrees EGTs pre turbo. Also, high RPMs causes the EGTs to go way up. Last year, before installing a pyrometer, I didn't know this and my RPMs going uphill was nearly 4000, I was getting very hot, and nervous.

This year, made changes. #1 went from eco tune to FT tune. #2 Got the transmission tow tune. #3 Taller and wider trailer (more wind resistance)

When pulling hills now (ones where trucks do about 35 for several miles), my temp climbs, but stops short for 3/4. This is a good pull at 55mph locked in 3rd gear doing 2600 rpm. No loss in power. I was considering backing off a bit if the temp rose any more.

I am considering putting a fixed race fan on mine and also hood louvers to try and get a little more air flow across the radiator and more underhood heat to escape.

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zoomcamper · **Joined:** Tue Jun 18, 2013 7:53 pm **Posts:** 9

New here but tow with my 2005 CRD an 18' Aerolite Zoom Travel trailer 3000# empty. The engine temp run half way on the gage with the A/C running in Ohio flat land. My CRD has had the gages reprogrammed by Jeep shortly after I purchased it (new). The reprograming corrected error in readings. I do not remeber the TSB#. I drive with the trailer at 62 mph, 1900 RPM in 5th gear and get 17 -20 MPG. In the hills of Southern Ohio it get 15-17 MPG and on long hills maintaining speed is not possible without the temp rising, dropping to 4th gear around 52 MPH the temp will rise to 5/8 and stay for the most part and I never run at WOT. If it goes above this I shut off the A/C, and it stops rising. :BANANA:

Our trailer in most trips weights in near 4200# with everything we take. Including 37 gallons of water. Some trips we take now we are not hauling the water depending on where we are going. The weight reduction seems to help the handing.

Been thinking of getting 4.10:1 gears installed to get the engine RPM up slightly and then fine tuning the engine RPM back to 1900 with different sized tires. To roughly equal the tire RPM with the stock 235 tires and the 3.73:1 gears running 57 MPH, this will reduce air friction.

Currently I have the GDE ECO tune but would like the full torque or hot tune. The GDE ECO tune was installed several years ago when I had the 2nd torque converter, now I have the English torque converter and no shutter.

DOC4444 · **Posted:** Tue Jun 18, 2013 10:52 pm

I would try the GDE tow tune and HOT ECU before springing for two new ring and pinions.

MUCH less $$$.......

DOC

zoomcamper · **Joined:** Tue Jun 18, 2013 7:53 pm **Posts:** 9

IThanks for the ideas on the tow tune, I would like to at least upgrade to the ECO FT. What does the tow tune give you?

DOC4444 · **Posted:** Wed Jun 19, 2013 9:13 pm

Ability to use 4rth gear up to 70 MPH. We get 32 MPG in 50/50 driving (NOT towing) with a gentle foot with the HOT tune. Just go easy when you do not need the extra power and you get the best of both worlds.

DOC

ChooChooman74 · **Posted:** Thu Jun 20, 2013 12:24 am

DOC4444 wrote:

Ability to use 4rth gear up to 70 MPH. We get 32 MPG in 50/50 driving (NOT towing) with a gentle foot with the HOT tune. Just go easy when you do not need the extra power and you get the best of both worlds.

DOC

Doc, how are you doing that? I am not even close... 25 or so. I am thinking my tires are a part of it.

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DOC4444 · **Posted:** Thu Jun 20, 2013 7:20 am

All the planets need to align and it needs to be summertime. Stock size, SL low rolling resistance tires 36 lbs, cold, no drag from brakes (several potential sources that only appear when hot), good thermostat, no VH, EHM so crankcase pressure does not build up, opened up exhaust, 5W-40 Mobil 1 in summer, GDE ECU and TCM tunes. (TCM tune adds 3-4 MPG between 35 and 55 MPH.) And, you need to correct the 10% odo error.

DOC

zoomcamper · **Joined:** Tue Jun 18, 2013 7:53 pm **Posts:** 9

10% Odometer error? HIgh of low? I know the speedometer is slow by 1.5 MPH comparied to the GPS.

I looked on the GDE web site, boy it has changed since I got my ECO tune. I drove up to GDE; Keith installed the tune. I think is was 2009 or 2010. I wouldn't like the tranny to shift into 5th at 70 as I rarely can drive that fast. I would like it to stay in 5th down to 50; 45 even better. If the tow tune would still shift into 5th at 59, then it would be OK but I would not get tow tune if you have to drive 70 to get into 5th, but the other tranny tune looks good. What I would like it to be able to lock-out 5th gear, with the button on the shifter, then tow in fourth (locked) when the need would arise. The button drops the tranny out of both overdrives so it is worthless. (My Libby had the F37 recall but not the tranny reprogram, as I asked the dealer not to reprogram the tranny, many shift points were changed to 64 MPH, If I knew the engine torque was going to be cut I would not allowed them to do that either. After the F37 when towing our Zoom I noticed the drop in torque right way).

My CRD get 22.3 around town, every week. On the highway at 70, 1950 RPM it gets 30.3, most of the roads around here are 2-lane state highways the speed limit is 55 but you can push 60 (NW Ohio is a training ground for the state police so you see them alot), I have gotten 34.2 on a 170 mile round trip, 2-lane highway without the trailer.

DOC4444 · **Posted:** Sat Jun 22, 2013 8:48 pm

If the odo indicates you have traveled 300 miles, add 10%, or 30 miles to correct.

The "regular" TCM tune shifts to 5th around 59 MPH. It locks the TC at 35 MPH and keeps it locked unless you exceed about 3/4 throttle.

DOC

ChooChooman74 · **Posted:** Sun Jun 23, 2013 8:33 pm

zoomcamper wrote:

10% Odometer error? HIgh of low? I know the speedometer is slow by 1.5 MPH comparied to the GPS.

I looked on the GDE web site, boy it has changed since I got my ECO tune. I drove up to GDE; Keith installed the tune. I think is was 2009 or 2010. I wouldn't like the tranny to shift into 5th at 70 as I rarely can drive that fast. I would like it to stay in 5th down to 50; 45 even better. If the tow tune would still shift into 5th at 59, then it would be OK but I would not get tow tune if you have to drive 70 to get into 5th, but the other tranny tune looks good. What I would like it to be able to lock-out 5th gear, with the button on the shifter, then tow in fourth (locked) when the need would arise. The button drops the tranny out of both overdrives so it is worthless. (My Libby had the F37 recall but not the tranny reprogram, as I asked the dealer not to reprogram the tranny, many shift points were changed to 64 MPH, If I knew the engine torque was going to be cut I would not allowed them to do that either. After the F37 when towing our Zoom I noticed the drop in torque right way).

My CRD get 22.3 around town, every week. On the highway at 70, 1950 RPM it gets 30.3, most of the roads around here are 2-lane state highways the speed limit is 55 but you can push 60 (NW Ohio is a training ground for the state police so you see them alot), I have gotten 34.2 on a 170 mile round trip, 2-lane highway without the trailer.

Keith can change the shift points. Mine is custom. I wanted 5th at 65 but due to speedo being off, it is shifting at 61. Sir Sam gave me one last idea to try at the dealership for them to try and correct my speedo. My first try at correcting it didn't work. If Sir Sam's suggestion doesn't work, then the TCM is heading back to keith for fine adjustment.

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zoomcamper · **Joined:** Tue Jun 18, 2013 7:53 pm **Posts:** 9

SO I really have 116,000+ miles on mine....

Next trip on the Ohio Turnpike I'll check against the mile markers, that spreedo error seem very high.

ChooChooman74 · **Posted:** Wed Jun 26, 2013 7:06 am

zoomcamper wrote:

SO I really have 116,000+ miles on mine....

Next trip on the Ohio Turnpike I'll check against the mile markers, that spreedo error seem very high.

I also use a program called GPS odometer. Compare all 3 and you will see how much it is really off.

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flash7210 · **Posted:** Wed Jun 26, 2013 7:39 am

When I was running some really tall tires, my odo was about 4% slow.
This was compared to GPS, google maps, mile markers, etc. so I felt confident about that error.

Now I'm running a shorter tire and its off by only 2%. Not enough to bother correcting.

papaindigo · **Posted:** Wed Jun 26, 2013 8:44 am

As with all vehicles, except those that have been "calibrated", the odometer and speedometer will be off. IIRC +- 5% is the industry accepted range of error. On the KJ the 2 gauges apparently get their data from different sensors so it's entirely possible to be off by different amounts and in different directs and of course installing tires that are in any way different from OEM can add another variable into the mix.

Bottom line is there is no way to say all KJ's are off by XX% (I've seen 4 KJs all off by different amounts for both speedo and odometer). If you want to be sure about what error you have, if any (ex. my speedo is essentially dead on but odometer is off), you need to do several runs of ca. 25 miles or more on a reasonably straight and flat road with a GPS to get accurate speed and miles driven. Recheck when new tires are installed. FYI don't count on highway mile markers being accurate, some are some are not.

GTS · **Posted:** Thu Jul 11, 2013 2:41 am

Sorry haven't gotten back to the forum to check up on my questions. I crested the hill at around 50mph or so. I can't imagine the fan clutch being an issue as I should be getting more air through the radiator from the speed than the fan could pull if it was engaged. Does the fan clutch really cause heat issues at 50+mph? I hit the bottom of the hill at 60mph or so and when it started pulling it down I kicked the OD off. I don't recall the rpm it was running but it was in the higher rpm range. I don't know the exact % of the grade but it's a moderate grade, not super steep but a good pull.

For those of you who have gauges what kind of boost do you see with a stock engine?

For those who are wondering a T@b is this. http://tab-rv.com/gallery/photos/.

naturist · **Posted:** Thu Jul 11, 2013 2:14 pm

I've got news for ya: when the fan clutch is engaged, it pulls a HUGE amount of air through the radiator, vastly more than you get just from moving forward. Unless you have the radio blasting, you will hear the roar when it kicks in, even above road noise at 60 mph. And unless you hear that roar, it hasn't kicked in.

Got hot while towing

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