Ok, I've got an odd situation here. I'm towing a travel trailer that weighs about 4500 lbs loaded and has about 60 square feet of frontal area. It's also 21 feet long, which doesn't matter here, but the last two days in 95 degree heat, it has been running hotter than I'd like.

Yesterday coming across the Alleghenies on the interstate, I kept the AC off and windows open so we didn't cook, and managed to keep the temp guage bouncing between normal and two-ticks-below-the-"H" mark only by letting it slow to as little as 45 on the up-grades. I'm not sure whether the 20-25 mph headwind helped cool it more than it added to the load.

Today the wind was mostly cross-wind, and in the flats but with the AC on, it mostly stayed at the 3/4 mark while cruising at 50-60 mph.

I know that there was a TSB about "overheating while towing in hot weather." That called for reprogramming the guage . . . obviously merely adjusting the thing so it read cooler than before. That was done on this vehicle.

It has performed ok, mind you, it just concerns me that it is running so hot. Is there anything I can do to help cool it off? Is there an extra-thick radiator core available or anything? Do I need to set the wife on the hood with a bucket of water to throw over the front from time to time?

There probably isn't anything wrong with your CRD... Its August and you are pulling something that while nowhere near heavy enough to bother the CRD, it has a huge amount of frontage. That is resisting the wind and making the engine work harder. The grades don't help either, I know those roads.

There is a small possibility that your fan clutch isn't engaging. If it did, you would hear a ROARING like none other. Honestly, I've never heard that from my CRD either, or from my v8 Jeep... The only vehicle I've ever heard it from is my 30' RV with a 454 and FIVE engine fans. 4 electric (two push, two pull) and the clutch fan. Usually the clutch fan isn't on, but driving in 100* heat 3 years ago, it was on here and there.

I wonder if there is a solid-shaft replacement option for our fans, that uses a flex-blade fan instead. I've had good luck with those as an upgrade from the clutch fan, and another benefit - They are a lot lighter, so use less energy to keep them turning.

What are you driving?

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'08 Liberty stock 4x4
'89 yj S.B.C., 700r4, np231, 8.8 rear end w/ yukon 4:10 gears. to many add ons to list

I do know that there are two fans available from the dealer, with "the other one" being the official towing package fan. I have also heard that it does cut fuel mileage, however, so since I seldom tow, I've been hesitant to do that switch. I understand that the swap also requires removing the radiator, so not something to be done but once.

We'll know more when we get to the southwest, I guess.

I'd like to hear from folks who have that other fan. Does it, in fact, help, and does it cut mileage or not?

A 2005 CRD, hiram.

all CRD's came with both fans - one electric and one mechanical (on gassers that was a tow package special - std on CRD's)
the 05 CRD's seem to have more problems with the mechanical fan engaging than the 06's
i.e. they don't engage as early as they should -and the fix is to replace the fab clutch


This was KeighJeigh's thread - although there were a couple of others
http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?p=373798#373798

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2005 CRD
stuff
Skeptic quod gratis asseritur, gratis negatur

See my thread about towing in 4th gear, runs cooler and get better fuel mileage.

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2006 Black Jeep Liberty CRD Limited
K&N, Samco Hoses, Michelin 245/70-16 LTX A/T2, Fumoto F-102, V-Force Muffler, Mopar, Hitch, Trailer Wiring, Skid Plates, Slush Mats, Rear Shelf, Predator Stage 1, Transgo, ORM & CodeReader, Facet 40109 Pump
"IT'S A DIESEL THING, YOU WOULDN'T UNDERSTAND"
Certified Services Auto & Truck Repair

I have the '05 and had both the fan clutch replaced and the gauge recalibration. When I tow in the summer on long uphill grades the gauge reads higher than normal. Probably not a concern.

The recalibration made a big difference in the gauge reading. I don't think the fan clutch replacement made any difference. My theory is that during highway driving the radiator gets enough air without the fan. It might make a difference in city driving, though. I have never had overheating in the City.

Here's the link that made all the differents in the world

http://www.lostjeeps.com/forum/phpBB3/vie ... ght=towing

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2006 Black Jeep Liberty CRD Limited
K&N, Samco Hoses, Michelin 245/70-16 LTX A/T2, Fumoto F-102, V-Force Muffler, Mopar, Hitch, Trailer Wiring, Skid Plates, Slush Mats, Rear Shelf, Predator Stage 1, Transgo, ORM & CodeReader, Facet 40109 Pump
"IT'S A DIESEL THING, YOU WOULDN'T UNDERSTAND"
Certified Services Auto & Truck Repair

That link shows there are a lot of people really confused about when our transmissions shift. Mine now shifts exactly as your does. It's a January 06 build and it originally had the earlier shift points. So there could still be some pre neutered 06 modles out there too They started the castration sometime in June of 06

I'll try your methode in the hills we to go through in West Virginia and Virginia this weekend when we take our 3500# travel trailer to the outter banks of NC. I'm hoping my GDE tune will make the drive more enjoyable I've towed it there twice and it has never overheated but the ambient temperatures were not over 90

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Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)

My hydraulic fan usually doesn't come on until engine coolant 220° ish and turns off around 212°. Temps start creeping up again and in 20-30 minutes on level ground it roars once more. I have about 7k miles pulling a 27' 5600# travel trailer with around 64 sq ft frontal at 65 mph. Mostly flat Michigan, but it has gone through the Smokies to Gatlinburg without major incident.

Usually I just keep my foot to the floor. It will chime at me if things get out of hand. Then it will cut power. If I stop going up the hill, it's time to pull over. Don't use the dash gauge to base your decisions, it lies.

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2005 CRD Limited Flame Red w/ Renegade rock rails & light bar, AirLift 1000. 225/75R16 MT/R's on cheap black steel wheels, dual MOPAR subwoofers, Ipod kit & seat covers, Samco hoses - totaled and gone. 2008 WK Laredo 3.0L diesel - AirLift 1000, wife won't let me mess with it much. 2013 JK Sahara on order.

Ok, read that thread, BL, and now I am confused.

Mine had the F37 recall done, and with OD on, it locks up while accelerating at 58 (indicated) and unlocks at 55 (indicated). I have not attempted setting the cruise by engine rpm, but will try that tomorrow. It should be noted that I'm currently in the flats of Michigan, where the speed limit is 70, unless you are driving a vehicle over 8000 lbs empty, for which it is 60. And the minimum allowed (on the interstate) is 55. I've been trying to hold it at 62 w/o cruise.

One of the messages in that thread you cited had somebody claiming to be getting 20 mpg with a trailer heavier, longer, and with more frontal area than mine. I have been getting 14 pretty consistently. It should be noted that when not towing, I have broken 30 on several occasions and with my general mix of in-town and open-highway, get about 25-26 most of the time. I would kill to hit 20 with this trailer.

Hmmmmm, burning all that extra fuel . . . I wonder if that is where all the heat is coming from?

Now you got the idea, set cruise by the tach not the speedo. Once shifted to fourth when near 60 MPH set the cruise. Then bump the rpm up a little at a time with the cruise increase switch until you hit 1975 rpm. Then it should stay in fourth even going down hill. Steep grades at 2650 rpm in third requires hitting the OD button and will cause temp to rise a little but much better than trying to lug it.

I towed like this from Montana to Washington and from Washington to Delaware and very happy with the results. I have the same thought that more fuel makes more heat so make sense keeping the engine at it most efficient rpm would run cooler.

Oh BTW, I saved at least three fill ups on the return trip to Delaware and $150+.

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2006 Black Jeep Liberty CRD Limited
K&N, Samco Hoses, Michelin 245/70-16 LTX A/T2, Fumoto F-102, V-Force Muffler, Mopar, Hitch, Trailer Wiring, Skid Plates, Slush Mats, Rear Shelf, Predator Stage 1, Transgo, ORM & CodeReader, Facet 40109 Pump
"IT'S A DIESEL THING, YOU WOULDN'T UNDERSTAND"
Certified Services Auto & Truck Repair

danoid,

How are you coming up with those coolant temps that correspond to fan clutch engagement/disengagement?

Thnaks,

DOC

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2005 KJ CRD Ltd Detroit TrueTrac Bilsteins G2 GDE "HOT" ECU GDE TCM "Tow Tune" "euro" TC SEGR Weeks Elbow New HG at 130K ARPs Clean CAT aFe Filter Magnaflow Exhaust EHM Cumminos In-Tank Lift Pump Hayden Fan Clutch Nylon Fan VH Enabled with GDE lower shutoff point Recalibrated Temp Gauge Tekonsha Prodigy Sears P-1 ZDDP

A scan tool.

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2005 CRD Limited Flame Red w/ Renegade rock rails & light bar, AirLift 1000. 225/75R16 MT/R's on cheap black steel wheels, dual MOPAR subwoofers, Ipod kit & seat covers, Samco hoses - totaled and gone. 2008 WK Laredo 3.0L diesel - AirLift 1000, wife won't let me mess with it much. 2013 JK Sahara on order.

Please see Danoid's response above.

Anyone know if a recent version of VAGCOM can read these temps on a CRD when in "generic" OBDII mode?

Danoid, what is your dash gauge showing when the scantool shows 220 deg (farenheit, I assume?) and do you know for sure whether your gauge cluster has been reflashed, or not?

Thanks again,

DOC

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2005 KJ CRD Ltd Detroit TrueTrac Bilsteins G2 GDE "HOT" ECU GDE TCM "Tow Tune" "euro" TC SEGR Weeks Elbow New HG at 130K ARPs Clean CAT aFe Filter Magnaflow Exhaust EHM Cumminos In-Tank Lift Pump Hayden Fan Clutch Nylon Fan VH Enabled with GDE lower shutoff point Recalibrated Temp Gauge Tekonsha Prodigy Sears P-1 ZDDP

My dash gauge has not been recalibrated.

From memory...

1/4 is about 90°
1/2 is anything from 130° to 190°
3/4 is about 210°
4/4 is about 225°

Soon after that you will hear a chime (same as your seat belt reminder) then you will start to lose power as the ECM cuts back on fuel to cut back on heat generation. I've hit that level twice*** - both times when I was going up steep grades too slow to lock up the torque converter in third (OD off). However, if the transmission gets to around 220° it will also go into overheat protection also and lock up the torque converter in 2nd gear. Magically this keeps the engine cooler also because you aren't throwing away 10-15% of your engine power (with an open converter) to go up the hill. IMO the torque converter should be locked up WAY more often than it is - but they didn't listen to me.

***Edit - oh, I forgot about the 2WD donuts - that will do it too...

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2005 CRD Limited Flame Red w/ Renegade rock rails & light bar, AirLift 1000. 225/75R16 MT/R's on cheap black steel wheels, dual MOPAR subwoofers, Ipod kit & seat covers, Samco hoses - totaled and gone. 2008 WK Laredo 3.0L diesel - AirLift 1000, wife won't let me mess with it much. 2013 JK Sahara on order.

This is a breakdown of the coolant gauge and where the needle falls for a given temperature. All temperatures are in fahrenheit.

As long as you're running the car and the needle is within the black portion of the gauge, hammer down. The engine is self-protecting and you need only hold it to the floor when towing up hills and so forth.

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Providers of wholly developed aftermarket solutions for the KJ CRD.
(248) 977 - 9531

I have a VAG-COM "HEX+CAN" interface and running current software in the obdii mode it will read most everything but the readings will be in celcius

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Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)

If your trans truly shifts into the last gear at 58, then you probably didn't get the flash that went with F37. That's the old shift point, which I still have. This technique of bumping up the cruise until 62 to stay in 4th doesn't work for us, because mine will not go over 1900 rpm (58mph) in 4th.

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05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.