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Discussion Starter #1
Hi All,
I have a 1997 Jeep Grand Cherokee Orvis Edition V8. It seems to have all options except for the surnroof. I'm not sure if it have the Class 3 or Class 4 tow package (Can anyone tell me what the difference is?) - The jeep did have the blue wire for trailer brakes and well as the Auxilarry Transmission Cooler AND I have installed the best trailer brake controller I could find (Tekonsha P3)

The Jeep has 155K miles and runs well. I have had it for over 40K miles and maintain it properly. The transmission is a little slow shifting from 1st to 2nd when it's cold (will wait until 3500rpm to shift)

The trailer is a 16*7 Haulmark Cadet enclosed trailer with a draw tite weight distributing hitch with the 550lb bars and the trailer has 2 3500 Torflex Axles, goodyear tires, and Trailer Brakes on BOTH axles.

I towed the trailer empty for 120 miles without the brake controller in 70 degree weather and my temp guage was giving me 210 degrees (normal is 190-195 degrees), obviously I was careful on the braking distances... and didn't have problems.

I towed the trailer full (between 6000 and 7000 lbs total - I will weigh it before doing the long trip) for 25 miles in 45 degree drizzly weather and was at 200 degrees. When towing, I kept it in 3rd at 50-55mph the entire time.

The jeep seemed to struggle a little getting up to speed, but was otherwise fairly stable, and the draft from passing trucks was not bad (I suppose this is because the trailer is fully loaded). I believe I was making about 9-10mpg on the highway, but got some 2 mpg on the console pulling it up a steep hill in town at 25-30 mph in 2nd.
The jeep, even with the load distributing setup does show some sag in the rear compared to the front, but not horrible.

My next tow is going to be for approximately 400 miles in 30-40 degree weather which has me a little concerned as it will be the 1st time I tow such a load (the most I've towed before was about 5000 lbs with a Uhaul trailer. I expect to tow at 45-55mph the entire way to reduce stress on the motor.

My questions are:
1) Does anyone know what the ZJ's maximum trailer frontal surface area can be (iirc WJ's can tow 60-68 square feet of front surface)

2) What precautions should I take to protect the transmission/engine.

3) I have a Factory transmission cooler. Should I swap it for a bigger one? If yes, what is a good size, and should I put a thermostat on it. I have a setrab 125 (small 25 row cooler) and a MOCAL an8 oil thermostat that I could use. Is the mocal appropriate and is the setrab big enough to make a difference over the stock one or should I not bother/go way bigger. The Jeep will be living in Canada eventually where it gets VERY cold in the winter (0F happens).

4) I will change the rear diff fluid to the heavier synthetic stuff. Is there anything else I should do to protect the rear axle/rear suspension. Would adding air helper springs make a huge improvement and if yes, where can I get them for the UP-Country Suspension package?

5) Is towing at 8-10mpg going to risk damage to external engine components due to excess manifold heat provided coolant temps stay below 200-250?)

6) Any other tips that you could give me for towing such a heavy load with the Jeep?

Thanks
 

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Discussion Starter #2
Here are the Trailer Specs:

Model CD716BT
Overall Length 20'5"
Width 84"
Height 99"
Interior Length 15'8"
Width 81 1/2"
Height 78"
Width Between Wheel Wells 76"
Platform Height 17"
Torflex EZ Lube Axles
Quantity tandem
Total Capacity 7000
Type drop
Brakes 4 wheel electric
Tire Size ST205/R15 -15"
Tire Load Range C
Wheel Bolt Pattern 5 - 4 1/2
Hitch Ball Size 2 5/16"
Hitch Height to Top of Ball 19"
Hitch Weight 350
Curb Weight 2870
GVWR 7000
Payload Capacity (Avg.) 4130

I have the jeep and the trailer already... If the jeep is deemed completely unsuitable, I might replace the Jeep with a Dodge Durango Hemi, but I really don't want to spend the money.

The Jeep is my Daily Driver and I really like it!
 

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the worst thng I ever did was use a stock 95 v8 ZJ to tow my 16' car hauler and buggy. Combined they weighed about 6000#'s and I had 10,000# load distribution, sway control, trailer brakes, etc. Used it for probably 5 trips to Moab (about 250 miles each way) and ended up burning up the tranny (even with OD off the entire time).

It's not that the motor doesn't have the power, it's that the vehicle is lighter and shorter than it's load, and the coil suspension doesn't lend itself well to pulling heavy loads. In a straight line on flat ground with no weather and no traffic, sure it's fine...or if you need to go short distances in a pinch, sure. But don't confuse that rig as a sufficient and safe tow vehicle for a 6-7000# load, no matter what Mopar wants you to think the tow rating is. the first time you encounter a situation where you need to stop or react quickly (god forbid in a snow or rain storm), you'll know exactly why the ZJ isn't a good tow vehicle for that load.

If you are going to tow often, I would look into at least a 1/2 ton truck. The durango is a step in the right direction, but still doesn't have the wheelbase to make that load manageable. Trucks are dirt cheap right now too.
 

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Discussion Starter #5
1/2 ton means 2500/250 correct... I'm really hoping to avoid a pickup...
Once that 400 mile pull is done, the trailer might be used to carry a 2300lb civic (5.5K lbs total...

I forgot to mention that the jeep is on 245-70 16 michelin tires and has hawk HPS pads all around.
 

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half ton is 1500. 2500 is 3/4 ton and 3500 is 1 ton

but a 1500 dodge truck shares much of the same running gear of a Durango, only it's longer and better suited to tow with.

I went from my ZJ to a 99 dodge 2500 short bed cummins, and I can't even tell you how HUGE of a difference that was.
 

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I pulled a Cherokee on a tow dolly behind my ZJ a few months ago and really wished I had had trailer brakes. I pulled another XJ behind my F150 Supercrew less than 2 months ago and I agree with Cody, the difference is night and day.

I thought even with the tow package and V8, the max tow weight was 6500#. You are towing right at the limits.
 

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The main difference between class III and class IV is capacity. Class III is up to 6,000 lbs in weight carrying mode and 10,000 lbs in weight distributing mode (i.e. with the spring bars attached). For class IV the numbers are 10,000 lbs and 14,000 lbs. Both typically have 2" recievers. It could be difficult to tell which hitch you have unless its on a label or stamped into the hitch. Note that the vehicle manufacturers tow capacity, not the hitch capacity, dictates your actual tow capacity. For ZJ's the manufacturers rating is 6,500 lbs in weight distributing mode with the V8 and auxilliary transmission cooler.

It sounds like you have a pretty good handle on what you are up against and the need to be extra defensive. Personally, I think the manufacturer is being a bit optimistic with the rating. During the summer I tow my boat which is about 4,500-5,000 lbs GTW. It tows OK locally. I once towed it up to Maine and back (160 miles each way) and probably would not do it again.

Good luck.
 

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Discussion Starter #13
THanks technohead, I'll go check on the hitch for markings.

For all others - I HAVE THE V8 AND the transmission oil cooler, AND a load distribution setup, AND a brake controller, AND Trailer Brakes on both axles. Please leave the I6 out of this discussion.

My initial questions were about whether increasing the Trans oil cooler and adding a thermostat were good ideas especially considering I will be residing in a super cold area.

As far as Towing capacity is concerned, in Europe, the V8 Jeep ZJ's are rated to 3500KG which is over 7700lbs. It's just that over there they tow at slower speeds. I don't expect to tow at 60mph. The Highway speed limit here is between 55 and 65mph the entire way and I intend to go around 50-55tops.

As far as towing is concerned, everyone here says to get a pickup. What are the reasons that the Jeep is not Suitable for towing and what can be done to improve the Jeep? It is my Daily Driver. I do not have the space or the resources to keep a daily driver + a tow vehicle + a weekend/race car... I love how the Jeep handles/feels on a day to day basis and will only be towing occasionally...

For Wheelbase:
The Jeep has a 106" wheelbase vs a 120" wheelbase for a normal 1500 series pickup to 150" for an Extended Cab... IS THERE A SPECIFIC RATIO OF TRAILER TO TOW VEHICLE THAT I NEED TO ACCOUNT FOR? I see pickups towing 24-28 foot trailers, and mine's only 16ft...

For Suspension:
Coils vs. Leafs - I saw that people don't like coils to tow, but the ride quality of coils is MUCH better. Would adding AIR helper springs resolve my coil issues?

For Chassis: - Is the reason that I can't tow because the Jeep has a flexy frame? Do I risk damaging/bending the frame/body by towing?

For brakes: the trailer has new electric drum brakes and is controlled by a great brake controller that can adjust brake force with accelerometers that are built into it. There is a manual override and when I tested it empty, it was able to lock the wheels fairly easily and when loaded, the trailer brakes can slow the entire vehicle down.

Anything else???

I am really trying to make the jeep more suitable and make sure it doesn't self destruct on me... I like it a lot and don't want a huge gas guzzling pickup for 500-1000 miles of towing per year...
 

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Discussion Starter #14
Cody, I just re-read your post about trashing the transmission... Would extra cooling have prevented the damage? Or is it a mechanical weakness in the transmission that makes it die quickly... I have a spare trans that's been waiting for a rebuild (got it for 25$ at Harry's U Pull It) Could I rebuild the trans with heavier load duty components or is the casing the weak spot.
Also what about the 249J? Will towing overheat it?
 

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I don't know the weak spot on the transmission, and mine had around 100k miles on it. I don't know what the temperatures were while towing because I did not have a trans temp gauge. I put one in my dodge and you would be surprised at when your trans would heat up...the worst is in stop and go traffic, or if you have to wait at a bunch of lights. Obviously it doesn’t hurt to have a bigger cooler, but that also will take more airflow from the radiator. I never had a problem with engine heat that I remember, but it does get old driving for a few hours with OD off (don’t tow that load with OD on) revved up to 3000 or whatever it was.

As for 6000# vs 7700# tow rating. Blah. The marketing department at Mopar can say whatever they want about it to make you feel safe, the fact is that IN MY OPINION, the ZJ is not a suitable tow vehicle for that load for all of the reasons I listed in previous posts. It's just not safe. I did it, it's not a power issue or a " I can't go xxx fast" issue, 98% of the time it will be less than desirable but OK, but it's that rare occasion that you encounter a situation where someone cuts you off on a major downhill and slams on their brakes....a deer jumps in front of you......a snowstorm while descending a narrow canyon road.....a major blowout on one of your 8 tires.....a trailer brake freezing up….traffic issue......any of a million things that can and will go wrong at some point if you tow enough that makes it a bad choice. Really, in the end it's an unnecessary risk, and you have to decide if the potential safety of yourself, those in the vehicle with you, and the people on the road around you is worth the risk. For me it wasn’t, so I took an absolute beating on selling my that DD ZJ to buy a suitable tow rig.

There is no scientific formula that I know of for WB of tow vehicle vs. WB of trailer as there are tons of other factors (weight distribution of trailer and/or tow vehicle, suspension, design of trailer, height of load etc etc etc). I had all of the things you mentioned (sway control, load distro, trailer brakes, tranny cooler, etc) and I would never use it to tow more than 4000# again.

You clearly have your mind made up about the situation, so just go for it. You're being proactive about it so thats a good thing. Just take it easy and you’ll get there and probably feel good about how you did what everyone told you was a bad idea and how we were all wrong. All of the situations I mentioned above have happened to me, and thankfully most of them occurred after I bought my truck as I'm positive that at least 2 of them would not have ended well had I been in the ZJ. But, I live at altitude and the route I towed had lots of climbs, canyons, and potential for bad weather. Maybe your situation is different. Just take it easy and don't get too comfortable.
 

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If you are going to do a lot of towing, and you don't want to go the truck route, have you thought about a different SUV, maybe a Expedition or Tohoe, or even a 2500 Suburban, or an Excursion?
 

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You clearly have your mind made up about the situation, so just go for it. You're being proactive about it so thats a good thing. Just take it easy and don't get too comfortable.
Probably the best advice in the entire thread if you are going to do it. Distribute your load properly. Even with my heavier WJ when pulling I experienced a bit of floating because of a poorly distributed load. Nothing will ever compare to trying to pull with my XJ, that truck almost put me in the Mississippi when I tried to tow with it. Next vehicle I buy will probably be bigger than the WJ.
 

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Discussion Starter #18 (Edited)
Thanks a lot for the advice cody... I do appreciate it. I might step up to something bigger eventually but being a city dweller, space for the cars is a problem... Plus justifying another gas guzzler just to tow the Honda (AKA the mistress) in the future will be a problem for me. In fact, keeping a gas guzzler like the jeep is already an issue as is, and my fiancee would be much happier with a smaller car/suv :-(

That said, you're right about me wanting to stick with the jeep. I love the car and will tow less than 1000 miles per year, and never in winter (except for the 1st tow in Feb/March which I will schedule on a clear weekend.

Since you seem to tow often, do you have tips to improve the jeep and make it (more) reliable/safer? I will tow the 6500-7000lb load once! Then will be going back to less than 5300lbs.
 

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6500-7k load is going to be heavy for a zj period. Take it real slow and give yourself plenty room to stop. I have towed with my zj quite a few times so I'm familar with what it can and cant do. I've towed a couple cars with it and I too have a 16' trailer. I would go with a larger tranny cooler and make sure you have no water/overheating issues. The zj is a mid size suv even though it has a v8. Its just not meant to do that kind of towing... Like stated before it can do a boat or jetski's etc no problem. But if you are trying to tow anything above 5k lbs a long way you are going to have to take it realy slow and careful.

I bought a 05' dodge 1500 and towing with it vs my jeep is night and day. Way more power and stability...
 

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question about the hitch on the v-8 ZJ's;

In the owners manual, it states that the v-8's have the class 4 hitch. I've owned two 5.2L grands, and this 5.9L. Both 5.2L Grands had trailer hitches, but no 7 pin connection, just a 4 pin plug for standard trailer harness. The 5.9L has the round 7 pin plug built into the hitch. Were the other two hitches class III's, and the 5.9L a class IV?

In the manual it lists towing capacity;
ClassIII = 5000lbs.


Class IV = 6500lbs.
 
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