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Beej
November 9th, 2004, 17:03
Hi all, I searched for the answer to this to no avail. I just got a new boat, and wonder if there is anything I can do to increase the tow capacity of my XJ? I can tow my boat, but I don't think I would want to roll on the highway over great distances with it. My Jeep is a 97 SE with a manual tranny and 8.25 rear axle. I will be installing a ford 9" in the new year. My other option of course is just to buy another truck to pull it with, but of course I'd rather roll in style in my XJ! Any thoughts, suggestions or flamings are welcome.
Thanks,
Brent.

Kejtar
November 9th, 2004, 17:11
Hi all, I searched for the answer to this to no avail. I just got a new boat, and wonder if there is anything I can do to increase the tow capacity of my XJ? I can tow my boat, but I don't think I would want to roll on the highway over great distances with it. My Jeep is a 97 SE with a manual tranny and 8.25 rear axle. I will be installing a ford 9" in the new year. My other option of course is just to buy another truck to pull it with, but of course I'd rather roll in style in my XJ! Any thoughts, suggestions or flamings are welcome.
Thanks,
Brent.
How heavy will it all be? I towed with my manual tranny equipped XJ close to 3K (2K lbs dry + spares/supplies) camping trailer out to moab. I had 4.11's with 31's and I made it without much trouble, although on all long climbs I kept saying: should have had 4.56's put in... should have had 4.56's.

erwinstein
November 9th, 2004, 17:13
yes you can first thing you do is hop into the jeep and drive to your nearest dealer and by a new truck thats the only way :laugh3: :laugh3:

Jackhill442
November 9th, 2004, 17:15
Well, if you had an auto tranny, the first suggestion would be a nice external cooler added, but I don't know if you can do that or not on a manual, but if you can, that should be the first. You should consider swapping the rear brakes to discs from a Grand Cherokee or buying a conversion kit, and getting an adjustable prop. valve to greatly increase braking power since much weight will be added to rear. Also, get cross drilled rotors and hawk brake pads for front. Next, add a cold air intake such as Rusty's Off Road to help the engine breath and be more responsive. Last, maybe add an addaleaf to the rear springs or a helper spring for towing. I personally added a Chevy Silverado full length add a leaf to mine while removing 2 of the factory leaves, and got about 2 inches more ride height and much stronger leaf packs. These changes may be expensive, but will make your XJ tow the boat more effortlessly. Also, I would air the rear tires up to about 40 PSI while towing the boat. Make sure the tires are strong and big enough. In the end, I would say braking will be your biggest need for improvement, though.

old_man
November 9th, 2004, 17:24
One of the considerations in calculating the towing capacity is simply the vehicle weight. If the trailer is too much bigger than the vehicle, it just gets too squirrely. I routinely tow over the vehicle's rated capacity, but then again I've been driving tow rigs for 40 years. That doesn't mean if everything goes to heck at once, that I'm not going to end up as road kill, but experience counts for a lot.

A load equalizing hitch will help a lot for stability. Make sure your trailer has brakes. Check your tire inflation and have good shocks. Increasing the sway bar diameter helps, and on a Cherokee, if you have the rear sway bar, keep it. Vehicle overheating is an issue on the actual pull. Like was said, if you have an automatic, add another tranny cooler. Rather than spend a ton on upgrading your brakes, get brakes on the trailer. It is a lot easier to stop it that way. If you have a sealed radiator system, I would think about switching over to a 3 row radiator and an open system configuration.

dallas xjs
November 9th, 2004, 18:35
not to hi-jack the thread but i have always wondered about this...i also have a 97 with the auto aw4,tranny cooler,456 gears,cat back 2 3/4 piping,k/n filter,throttle spacer,header,stanless brake lines..when towing i use 31in all terrians.74000 miles on truck..when towing my boat{18 ft single axle no breakes} it tows easy and smooth...towed boat once 7 hrs one way out of town without 1 problem..heres my ?..i have been been thinking about a hardcore trail rig with a 18feet double axle trailer with breaks...with my set up is this possable to tow trail rig short/long travels??or should i also drive to the dealership and get a tow rig???||charles||

orvpark
November 9th, 2004, 18:43
get out your checkbook, an xj would have problems pulling the trailer you describe let alone having a rig on it

WobblesXJ
November 9th, 2004, 18:45
Extend and widen your wheelbase for stability. Get a small block and better transmission. Regear. Or just buy a tow rig.

xj92
November 9th, 2004, 19:22
Sleeve the rails, replace the rockers with box tubing, integrate a roll cage into it. This will add weight and increase what the frame rails themselves can handle where the hitch attaches. Then swap in larger axles with better brakes and lower gears. Then swap in a different brake booster and stiffer springs and you should be set.

XJ_ranger
November 9th, 2004, 19:28
Sleeve the rails, replace the rockers with box tubing, integrate a roll cage into it. This will add weight and increase what the frame rails themselves can handle where the hitch attaches. Then swap in larger axles with better brakes and lower gears. Then swap in a different brake booster and stiffer springs and you should be set.
you just said the same thing as

yes you can first thing you do is hop into the jeep and drive to your nearest dealer and by a new truck thats the only way :laugh3: :laugh3:

Beej
November 9th, 2004, 20:19
Thanks for all the responses so far, keep them coming if you got more. It has a manual transmission, don't know why I didn't mention it. It also has a 3" lift with a newer flexier rear pack going in pretty soon as well as some coil over shock overload springs (a great recommendation from Eagle - tx). The Ford 9" I think I will be installing has discs so that should not be a problem. I figured that vehicle weight would play into it, I just wondered if it was something that would be possible to upgrade relatively easily. The boat is 19.5', with trailer its about 3700lbs. The trailer does not have any brakes, so I will look into a surge brake system for it. I also don't have load levelers, but I should look into them too. Anything else?
Thanks,
Brent.

nhrocker
November 9th, 2004, 20:45
First, you did mention the manual tranny.

Second, are these "great distances" all flat, or are you dealing with hills?

If you are you should look into boosting your power. Look into the exhaust, air intake, programming chips, throttle body, the list goes on, but you get the idea. The more power the better! :D

Kejtar
November 9th, 2004, 21:12
The trailer does not have any brakes, so I will look into a surge brake system for it. I also don't have load levelers, but I should look into them too. .
I don't know how surge brakes work but if they are not tied into your brakes into the jeep forget it: you want something that will allow you to override and brake just the trailer in case the trailer decides to try and overtake you (or rather go in a slightly different direction due to win). The camping trailer I towed had plain electrical brakes which worked great and the prodigy controler did all the work in regards to regulating the "braking force".

You might want to visit a place that sells bigger camping trailers and see what they have for brakes in a similar weight group and go from there.

Root Moose
November 10th, 2004, 07:20
Holy crap - what has happened to the signal to noise ratio in this thread? Very un-NAXJA.

Anyway, I did some research into this recently. Some of that can be read here: http://www.naxja.org/forum/showthread.php?t=36266. I decided to go the PU route because of the weight and U-Haul wouldn't rent me the trailer with the load I need to move.

If'n it was me, I'd try to make your XJ do the job. If your trailer is only ~3700 lbs you should be able to get by as long as you are intelligent about it. Look into electric brakes or surge brakes on the trailer and also look into a load leveling hitch. That should keep the ass end from dragging and make the drive more pleasant and the brakes on the trailer will keep the braking load off the Jeep.

Just my spin.

r@m

Beej
November 10th, 2004, 08:06
Thanks again guys.

+ I will be pulling it all over hills and straights; think rocky mountains and coastal mountains plus huge rainfalls and slippery highways.

+ Kejtar - thanks. Surge brakes are trailer mounted brakes, the trailer hitch coupling itself acts as a brake pedal, when you hit the brakes in your vehicle, the trailer moves forward compressing the hitch coupler and applys pressure to the trailer brakes. They work very well, I have used them on snowmobile and camping trailers over the years, I just did not think about using them before I posted this thread.

Anything else anyone?

B.

Kejtar
November 10th, 2004, 08:29
+ Kejtar - thanks. Surge brakes are trailer mounted brakes, the trailer hitch coupling itself acts as a brake pedal, when you hit the brakes in your vehicle, the trailer moves forward compressing the hitch coupler and applys pressure to the trailer brakes. They work very well, I have used them on snowmobile and camping trailers over the years, I just did not think about using them before I posted this thread.

Given your description I'd probably put on electrical brakes instead. With those you have the ability to stop sway as you can apply brakes on the trailer without applying the brakes on the vehicle and you can also control the brake "Force" between the two (vehicle brakes harder then trailer, same as trailer or less then trailer) which comes in really handy in mountains, on wet surface and in windy conditions.

XJJack
November 10th, 2004, 08:31
You say the trailer does not have brakes at all, so you will have to change the hubs to ones with brakes, you would also need to rework the tounge of the trailer for a surge brake mount, it will be cheaper and more efective to go electric and be able to control it remotely.

scoobyxj
November 10th, 2004, 10:01
Thanks for all the responses so far, keep them coming if you got more. It has a manual transmission, don't know why I didn't mention it. It also has a 3" lift with a newer flexier rear pack going in pretty soon as well as some coil over shock overload springs (a great recommendation from Eagle - tx). The Ford 9" I think I will be installing has discs so that should not be a problem. I figured that vehicle weight would play into it, I just wondered if it was something that would be possible to upgrade relatively easily. The boat is 19.5', with trailer its about 3700lbs. The trailer does not have any brakes, so I will look into a surge brake system for it. I also don't have load levelers, but I should look into them too. Anything else?
Thanks,
Brent.
I thought Cherokee's where rated for 5000 lb. from the factory. So IMHO with Ford 9'', rear discs, and the proper gearing, I wouldnt worry about it. The breaks on the trailer would be a given though.

Kejtar
November 10th, 2004, 10:02
I thought Cherokee's where rated for 5000 lb. from the factory.
for aw4, the ax15 is 2000 or so

Lawn Cher'
November 10th, 2004, 10:52
A 3700 lb boat/trailer package is manageable for an XJ with proper gearing, suspension & brake modifications as discussed previously, but you must put hydraulic surge brakes on that trailer! Electric brakes are not an option for a boat trailer (ever launched a boat, Kejtar?) There are electric-over-hydraulic brake systems available, but they are very expensive. This would give you the ability to use a brake controller for manual override, but boat trailers are inherently less prone to sway due to the long tongue length, and work very well with standard surge brakes assuming they are properly maintained. This long tongue length generally puts a substantial tongue weight on the tow rig, which is where helper springs, airbags, and/or a weight distribution hitch comes into play. Doing this on a lifted XJ only hurts you with the raised COG, bigger tires, flexier springs, and commonly deleted rear sway bar.

Having a larger, heavier tow rig provides a substantial margin of safety... instead of fighting with a squirrely rig and getting there exhausted, the increased wheelbase, track width, weight, braking capacity and suspension capacity will make the trip much more pleasant and trouble free so that you can better enjoy your boat when you arrive. XJ's have plenty of power, but the other areas of tow vehicle consideration are seriously lacking for any substantial trailering loads.

The first time you have to make an emergency stop on a wet mountain road with a heavy trailer in tow, you'll be thankful for the extra safety equipment you've invested in. Remember kids, be safe out there. It is not just your life on the line. :lecture:

Kejtar
November 10th, 2004, 10:59
Electric brakes are not an option for a boat trailer (ever launched a boat, Kejtar?)
Ooops.... forgot about the wet stuff :D

fumble
November 10th, 2004, 14:06
What about pulling a trailer with 2 sleds on it with the 2" RE Budget Boost on a 01 XJ Limited. Shouldn't be a problem, correct?

Kejtar
November 10th, 2004, 14:14
What about pulling a trailer with 2 sleds on it with the 2" RE Budget Boost on a 01 XJ Limited. Shouldn't be a problem, correct?
wel... how heavy is the trailer with sleds? stock tires? stock gearing? this all affects it. For example if you got stock gearing and 32" tires you will have trouble pulling something up hill that you'd fly with on 225's.

fumble
November 10th, 2004, 14:23
245/y5/r16 stock gears, no idea on weight of sleds. Just thought I would throw it out there to see if anyone is towing sleds at this time

Lawn Cher'
November 10th, 2004, 14:32
Well, a 245/75R16 is about the same size as a 31" tire, so with stock 3.55 gearing you are already taxing the vehicle somewhat, mostly the transmission and brakes. You could probably get away with a couple of sleds on a light trailer, but I'd definitely want electric brakes on that thing since you'll be in snow country, and a transmission cooler. It would be beneficial to keep the rear sway bar in place, and add extended bumpstops. 4.10 gears would be helpful as well, but that is more involved and costly.

fumble
November 10th, 2004, 14:56
Yeah I guess I'll address all that if I get the sleds

Well, a 245/75R16 is about the same size as a 31" tire, so with stock 3.55 gearing you are already taxing the vehicle somewhat, mostly the transmission and brakes. You could probably get away with a couple of sleds on a light trailer, but I'd definitely want electric brakes on that thing since you'll be in snow country, and a transmission cooler. It would be beneficial to keep the rear sway bar in place, and add extended bumpstops. 4.10 gears would be helpful as well, but that is more involved and costly.

Beej
November 10th, 2004, 15:23
Thanks for all the input everyone, I appreciate it and it helps. I'll keep posting up any mods I do to address this issue to help others who are doing something similar.
Thanks again,
Brent.

Rev Den
November 10th, 2004, 15:34
Anything else anyone?

B.


No, you can't safely do it, it is a very bad idea to try to overtow with your XJ.

flamings are welcome.

OK...I feel dumber just participating in this thread, buy a damn truck and get real.

Beej
November 10th, 2004, 21:58
No, you can't safely do it, it is a very bad idea to try to overtow with your XJ. OK...I feel dumber just participating in this thread, buy a damn truck and get real.I appreciate the vehemence with which you respond, however, would you indulge me with a little elaboration?
B.

8Mud
November 10th, 2004, 22:30
Just throwing my $.02 in. Germans do a lot more towing than you normally see in America. They pretty much have all the manufacturers standardized (everybody uses the same system). The towing tables are pretty much universal. Germans do trailers well.
They say my XJ, can tow, 4840 lbs. with surge brakes. Max speed 50 MPH.
My personal limit, is to match the wieght of the XJ. About the wieght of the boat and trailer you have. I put mine on a scale, why guess.
Most of the coil over shocks I´ve seen, are a fairly anemic shock, surrounded by a spring.
After a few experiences with a tonque heavy trailer, I´d be looking seriously at a 3/4" or 1" rear sway bar (Hellwig?).
Never tried it on an XJ, but Air Lift, coil over air bags, worked great on my pick up (I hauled a fork lift around). With the air removed and just the helper coils, it actually ran smoother than stock.
Think most of your problem will be frying clutches and tranny parts. A dual diaphram booster, rear discs and lower gears, would sure help, in the Rockies.

junkxj
November 10th, 2004, 23:04
In my experiance I would not tow anything heavier than my xj. That is with a brake controller, and good trailer brakes. THis is not for the 99% of the time every thing is good, just for the times that stupid happens. Just my opinion.Like stated earlier, if in question, why risk your saftey and other people on the road. I don't mean to preach, just heard of too mean towing accidents.

Blackash132
November 11th, 2004, 00:15
sell the boat and get a waverunner, that should be light enough to tow without a problem, besides with the money you save get some cool stuff for your XJ!:lecture:

Rev Den
November 11th, 2004, 01:25
I appreciate the vehemence with which you respond, however, would you indulge me with a little elaboration?
B.

Yup. Your XJ was designed to tow a maximum weight...period. Unless you are going to re-construct the whole vehicle, including frame, axle, springs, driveline...etc. you should stay within the factory limits. People overtow all the time, many without any problems, some end up in ditches. Your original question asked if you could increase your towing capacity. I tend to advise on a more conservative level, so my answer is "no". If you need more towing capacity the logical choice is a vehicle better designed, from the ground up, to tow....in short, a truck.

HTH


Rev

Kejtar
November 11th, 2004, 06:32
Yup. Your XJ was designed to tow a maximum weight...period. Unless you are going to re-construct the whole vehicle, including frame, axle, springs, driveline...etc. you should stay within the factory limits. People overtow all the time, many without any problems, some end up in ditches. Your original question asked if you could increase your towing capacity. I tend to advise on a more conservative level, so my answer is "no". If you need more towing capacity the logical choice is a vehicle better designed, from the ground up, to tow....in short, a truck.

Rev... are you talking about 2K limit or the 5K limit now? Cause the issue here is I think that Beej wants to tow over 2K but under 5K (I hope under 5K)
with a manually equipped XJ (hence the 2K limit). Also the main differences betwen the stick and auto models would be gearing which I think are the cause of the 2K limit and if he regears those issues go away (worst case scenario he needs a new clutch sooner) and IMHO he should be fine to tow up to 5K (or as fine as an auto exquipped vehicle would be) as long as he observers all the other safety and towing rules.

bgcntry72
November 11th, 2004, 07:03
Towing capacity?
Dual exhaust?
I think you may have purchased the wrong vehicle.
It is an XJ, not a cabover Peterbuilt.
HTH.

Beej
November 11th, 2004, 08:55
Towing capacity?
Dual exhaust?
I think you may have purchased the wrong vehicle.
Simple questions about towing capacity that have now been answered, thanks, but I just did not know.

Dual exhaust was a chance to help some kids and get some cheap/free work, again, I just had to ask as I did not know.

Last I checked, asking is the best way to get answers. I appreciate yours too, even if a little judgement is attached...;)

Thanks everyone, I have my answers, naxja rocks!
Brent.

bgcntry72
November 11th, 2004, 10:01
:wave:

Rev Den
November 11th, 2004, 12:25
Rev... are you talking about 2K limit or the 5K limit now?

It matters not grasshopper, the original statement as stated...stands.
:paperwork

Rev

Big Red
November 11th, 2004, 13:22
Wow, people really posted up on this 1. All that has been said is good advise. I know with the manual 5 speed you get 3.07 gears stock, which doesn't give you a whole lot of power.

I'd swap those out and go with 4.11 or 4.56 gears and a xj dana 44 rear axle for more strength. A ford 8.8 would actually be a little bit better because of its size, strength, and disc brakes from 95'+. The ford 8.8 would really help along with 4.10 or 4.56 gears. You can get a ford 8.8 with 4.10 gears and a track lock for not much more than an open 1 with 3.55 gears.
Troy

pbureau
November 11th, 2004, 14:30
you can tow safely 5500lbs if you have brakes on the Trailer, using a Class III/IV Hitch hoocked up with Load balancing setup (adds 1,000lbs per bar), anti-sway (left/right_ sway bar hookup (great on highway drives + windy days keep the trailer behind you straight and removes any "squirly" feeling the rear end would have) , stronger rear sway bar, Stiff Suspension (ie: AAL + rancho 5000 is great for hauling) , I personally prefer Electrical Brakes to proportional Brakes, because the proportional valve system is pretty much.. on/off... the electrical system can be adjusted (depending if your just hauling the empty trailer or you have 20 bales of hay or 2 horses you get the picture) and also permit control on when brakes are applied (Ie: I can turn the brakes on the trailer manually (some newer models also permit other variabnle options according to pedal pressure) and permit to hold a straight line in a hill with snow for example) knowing how your vehicle runs, and how to tow and how both interact with each other is important, that way you can expect problems befoire they arise..

PS: 5 years of haul tractor/trailer woke the heck of me :)

As fopr protection on engine and Transmission if you are going to haul 3500-5000 load on your jeep I strongly suggest External Oil cooler for BOTH engine and Transmission, switch your Differential oil from 75w90 to 140w90, this will also keep the rear end very cool and not burn up with time.

cheers