Comanche Dd And Towing Rig

[JustinT]

Hey everyone I'm new to comancheclub. Just had some questions and maybe throw around some ideas with you guys. I've had 3 xj's and 1 zj but I've always wanted an mj. I'm very familiar with the unibody construction of these jeeps because they are pretty similar to the xj's by I know they have they're differences. What I wanted to do is tell you guys what I want to do and let me know what you think, and criticisms or ideas that would help. here's basically what I want this jeep to do.... I want an mj that is very durable, has a nice interior, and can haul a car dolly with at most a 1/2 ton shortbed 4x4 squarebody Chevy.

I have about a $10k MAX budget this will be my first decent vehicle I've ever owned I'm 19 and want a nice rig. Here is a rundown of what I want to do to this mj and I have PLENTY of tools and am a skilled mig and tig welder and am very mechanically inclined. I will be doing all my own work.

 

97-01 cherokee interior swap including doors

Rebuilding my current 92 xj 4.0,ax15,np231 running gear to go in it

Getting a 4.7 stroker kit with 4.2 scat crank and 99+ intake

Full OBD2 swap with the interior as we'll

4.5" lift and 33" tires

Chrysler 8.25 with zj disk conversion from 92 donner xj

Dana 30 from 92 Donner xj if mj I buy isn't factory 4x4

Full Yukon 3.55 gears as well as axle shafts front and rear

Possibly ARB locker in rear

Custom build slip tank in bed for long hauls + free fuel from work

Dual optima yellow tops with isolator and h.o. Alternator.

And many other small things

The motor will be a 4.7 stroker with new cam, hydraulic lifters and roller rockers etc.

 

So what do you guys think? I'd like to use it for a daily driver as well as road trips and hauling other jeeps and such between North Dakota and Colorado. Any input on towing upgrades? Tips for the interior swap? Or general input and criticism?

Thanks guys!

[Eagle]

1. Do not put a locker in a tow rig. Limited slip, okay. Locker ... no.

 

2. An MJ is too small and too light to be towing the load you are describing.

 

3. 3.55 gears with 33" tires will be a horrible combination. 31" tires with 3.73 gears is the exact same final drive ratio as stock tires with 3.55 gears. 3.55s with 33" tires will be significantly worse than stock tires with 3.07s. You need at least 4.56 gears with 33s.

[Oyaji]

Pulling is not the problem - being able to maintain control and stop safely is.

 

Being safe in normal traffic encountered on public roads should be the over-riding concern. I've gotten by on flat-land deserted country roads with too insubstantial a truck pulling too-heavy loads of farm equipment, and even then drove at extremely low speed (~25 mph average, maxing at 35 on miles-long straights). Even then, it was always a bad white-knuckled driving experience, only done because I had no alternative. Such is not ever to be recommended.

[johnj92131]

This question comes up 3 or 4 times a year.  Here is a 3 page thread that you should read for answers to your questions:

 

http://comancheclub.com/topic/40651-what-breaks-in-a-boosted-40l/?hl=towing

 

The VERY short answer is that the Comanche, EVEN when properly equipped has a maximum tow rating of 5000 lbs.  Key word here is properly equipped.  Your proposal is properly equipped to to a maximum of 2000 pounds, per the factory.

 

One more thing, your $10K budget will not cut it.

 

Here is a partial list of what you need for a properly equipped Comanche to tow 5000 pounds per the factory:

1)  Long Bed - not short bed

2)  Automatic Transmission

3)  Power Steering and Power Brakes

4)  Heavy duty radiator and transmission cooler

5)  Dana 44 axle (it comes with wider brakes than the Dana 30)

6)  Class 3 hitch  (No longer Available new)

7)  Equalizing hitch

8)  Trailer with less than 25 square feet front area.

9)  Big Tonne package or Metric ton package includes all the above.

 

There is more you need, but as you can see, your build does not include a single thing the factory says you need.

 

Last thing, the Gross Combined weight for the Comanche and trailer (with the Metric Ton package) is about 9200 lbs.  Your extra battery, extra gasoline tank/fuel, big tires and wheels ALL count to that 9200 lbs and reduce what you can to with the properly equipped truck.

[JustinT]

Ok guys I appreciate your guys input and criticisms. It was exactly what I was looking for. But there are some things I wanted to reply to

1) to eagle: stock 5 speed equipped xj's and mjs come with 3.07s. I know xj's do but if mjs don't please correct me and my xj was 5speed swapped and I have 3.55s with 31s and a 5speed and 75 on the freeway is spinning about 3200 RPMs and me no likey that.

2) to john: ya I was planning on a long bed, if j put short bed in there that was a mistake haha. I refuse to drive an automatic haha I'm a stick shift guy every day. I could probably do an NV3550 out of a tj, they're a bit beefier than the ax 15s

 

So scratch the towing a full size Chevy. I'm selling it next week. I think you guys think this jeep is going to have a lot more toungue weight on it that if actually is. At most now it will tow my project xj's zj's wjs and cjs from Colorado to North Dakota and back. Even with a fully loaded v8 wj on 33s will only be a toungue weight of about 1200-2000 pound on a 2 wheel car dolly. And as shear brute torque goes I pulled my bros old k20 Chevy on 35s 128 miles up hill with the 92 xj I have now. Granted I was 2nd gear the whole time but it still got the job done. All I needed was a tow strap and him slowing me down on grades.

 

I know I'm probably gonna favs to bump my budget up...classic jeep owner saying.... But it'll be worth it.

And this jeeps gonna get full disks all around AND an electric brake booster aid as well a stealer brake controller. My dolly has electric drums on it.

[kq.echo.413]

I understand you want a Mj tow pig...however I'm just chiming in my idea..at the money you are going to spend you could buy a used dodge diesel and a used gose neck trailer and pull all your stuff with ease and safely.

[Eagle]

 

1) to eagle: stock 5 speed equipped xj's and mjs come with 3.07s. I know xj's do but if mjs don't please correct me and my xj was 5speed swapped and I have 3.55s with 31s and a 5speed and 75 on the freeway is spinning about 3200 RPMs and me no likey that.

 

Impossible. With 3.55 gears, 31" tires at 75 MPH run 2250 RPM, nowhere near 3200.

 

However, whether you like it or not, at 75 MPH 3200 RPM is about where you should be. The basic engine design goes back to AMC in the days before we had overdrive transmissions. Factory gearing typically was 24 MPH per 1000 RPM ... which meant that 2500 RPM was exactly 60 MPH, and 3000 RPM was 72 MPH. My brother had a Gremlin set up like that. Even with autocrossing it to two state championships it still went well over 300,000 miles.

 

3.55 gears with 33" tires is a lousy setup even without towing. For towing, it's completely unacceptable.

[JustinT]

I don't think that 3:55s and 33s would be that bad for towing cuz I have 3:55s and 31s on the xj I have now and have towed a couple of previous xj's to the junk yard on my 15 foot flat bed. It didn't want to stop or steer very well but it towed it without any bogging. And you have to remember that 5th gear in an ax15 is a different gear ratio as overdrive in a stock aw4. So I spinn about 3k at 75 with my 31s and 3:55s. And I know they are 3:55s because I had to replace the r&p in the rear end from previous owners $#!&ty sealing job on the dif cover. All fluid drained out and when I got stuck up to the dif in a mud hole overnight I drove it home and 1/2 way there my rear axle started groaning then BAM! and the tires locked up. Checked the breather and it was fine then took the cover off and my r&p looked like it went through Hiroshima. So now my 8.25 has a very nice pretty Yukon axles r&p kit yay!

[Oyaji]

Simple maxim: "It's easy to go, but hard to stop."

 

Even stock 4-cylinder power is enough to get you going plenty fast enough to get into trouble. To reiterate what I mentioned before, emphasis should be on control and stopping ability before all else.

[JustinT]

And as a response to echo... I honestly don't like very man diesel trucks and here are my reasons

Chevy: I refuse to own indiependant front suspension on ANY of my vehicles

 

Ford: the 7.3 idi and the 7.3 powerstroke are great...my dad owns both. But I don't like the looks of them and the 6.0s are awful awful motors...dad has a blown up one in his back yard on its 2nd motor and the 6.4 and 6.7 are way outta my price range.

 

Dodge: I love the 12valve and 24valve cummins but I'm not big on their body stylings and as EVERY chrystler auto transmission goes they are crap. The transmissions behind cummins motors, behind i6 & v8 zj's and wjs, and even just the dodge 1500s.

 

Unless you like the 90-03 body style fords...yes I know there's 3 styles in there, you really can't win when it comes to diesel trucks.

 

Chevy: crap front ends

Ford: ugly

Dodge/cummins: trannys are crap.

 

I also am picky about them because I live in ND and these roads tear trucks apart. The life expectancy of a new truck up here is about 8 years.

[JustinT]

Oyaji you have a great point. That is the main concern here. That's why I have a car dolly with electric brakes. And this mj will get disks all around plus an aftermarket electro/pneumatic brake boosters as well as the upgraded (I believe 94+) brake booster. The ones factory on zj's that have the plastic reservoir. And a car dolly has almost no tounge weight worth talking about even with a car on it, so I won't have a front end lifting problem you get with many overloaded trailers on smaller vehicles. I won't have the front end lifting upso much that I loose traction in the front end and if I do it won't even be enough lift to be noticeable handling wise. I've done the same stuff I'm talking about here with my xj quite a bit I just wanted to know of any possible problem I might run into while doing this many times (1500 miles each month) for a while.

[COMJNUT]

I've done a lot of towing with mine, from a 93 chevy lumina on a dolly, countless jeep cherokees, a lead sled lincoln, or a good size trailer(a pic is in the MJ's earning their keep thread). I have a 98 D44 with disks on the rear and it does good, but it leaves much to be desired in stopping distance with a load. Upgraded brakes are a must, there is no such thing as overkill on the brakes when you are towing. I would look for full size P/U axles for strangth durability and the brakes.

The 3.55 gears are not adaquite for towing with 33" tires, even if you had swapped a 5.9L from a 98 grand into it. I'm at 3.73 gears with a stock motor and a good size load slows me down and is hard to accelerate with the 32" tires that I have. If I was regularly towing weekly, I would want to change the gears to 4.11 or 4.56.
 
Better idea for a tow rig: restore a J truck, it has a better towing capacity, beefier axles, just to name a few positives.

 

 

Edit to add: yes a log bed would be better for towing, beefier leaf springs with the metric ton package(you can get better ones from alcan than stock) to add to what was previously said.

[Oyaji]

You seem fixed on the idea, so here are a few tips (you probably know them already, but it doesn't hurt to repeat them here, and to repeat them to yourself every time you take to the road laden):

• Towing is always more risky than just driving without a trailer, but any sort of driving has attendant risk. The more miles you drive, the greater the risk exposure. (I know, I know - how else are you going to get experience, right? But focus on safety and keeping speed low is never misplaced. My dad drummed that into us when I was a kid, impressing on my brothers and I that the family farm was at risk every time he sent us out driving ridiculously overloaded vehicles. But in our 4 combined driving lifetimes totaling 180+ years and an estimated 4 million+ miles, we have never had a crash.)
• Trailer brakes are great, but you still need to be able to stop safely if they fail.
• Car dollies aren't supposed to be used at speeds over 55 MPH (and for good reason: they tend to start "whipping" if you get faster than that, and can even exhibit this tendency at only 35 MPH).
• Any time you modify brakes, you need to do your own testing to ensure you have set up proper brake bias to avoid early rear axle lockup (an adjustable proportioning valve is required). Keep in mind that if you crash and there is an investigation of your vehicle, you just might be in for a world of pain - burden of proof will be on you to demonstrate that your tow combination was safe. (Even with the best and most diligent testing, you'll probably have a very difficult time convincing the court that your evidence is as compelling and valid as the factory letter of compliance with the federal brake standard - but you'd be completely screwed without it. You'd be best advised to go with the best OE factory standard tow package - and to not exceed its limits.)

I'm sure there is much more to be said, but these thoughts come to mind right off the top of my head...

[MrSimon]

If you want to do regular towing of full size vehicles ..... get a truck designed to do it.  

 

Your MJ build looks great (go with deeper gears though) and I think you should totally do it ..... but don't use it to tow a truck on a regular basis.  Its just not safe.  Once in a while for short distances if you are in a pinch - maybe.  But not as a dedicated tow rig.

 

My advice is to get a nice 5.3L Suburban with higher mileage for around $5k to use as a tow rig (you really need to get past the independent suspension thing) and spend the other $5k on your MJ.  Best of both worlds baby!!!  

 

I can't tell you how nice it has been to have a reliable tow rig that can be used as a driver while the Jeep is laid up. 

[JustinT]

All of my dreams are being crushed! Haha I knew that's a Comanche "towing rig" wasn't necessarily a TERIFIC idea but just somthing to ponder on. I like Comanches and I like project jeeps that I can flip for a profit and I thought if I'm going to sell jeeps why not show up in a really nice one and show what a jeep can do. Idk I'm wired like that I've been looking into building a

Crew cab Comanche

14bolt narrowed to jeep width

Dana 60 front jeep width narrowed

Chevy 454 with nv4500

Unibody fully strengthened and boxed

35's

Now that would be a fun dd/tow rig but that 20-30k I'll spend in 5-10 years lol

 

I might be scratching my mj idea for a while cuz I think I found my first jeep I sold a while ago it's a 1988 Olympic edition pioneer xj with 4.0 auto blue interior manual locks windows and factory sunroof. If I can buy it back I'm gonna build it I found it in pueblo co but I sold it a while back in aurora co.

[johnj92131]

I have had one accident while towing a trailer.  It was in 1999/2000.  I was towing a 4000 lbs  camping trailer about 12 miles to home.  I had to travel about 7 miles on good, wide California freeways in San Diego.  I was traveling north on 163 merging with I-15.  It is a very gentle turn where the 2 freeways merge into one.  At that point the freeway is 8 or more lanes wide.  My trailer had just a bit too much weight on the @$$ end, so it started dancing around and I could not recover control by mashing the throttle.  I wound up using the brakes to stop but wound up on the side of the freeway facing the wrong way.  The trailer had turned the SUV 180 degrees around.  Single car accident.  Lucky the Saturday morning traffic was extreemly light.  The only thing I did not try was to jamb on the trailer electric brakes.

 

The SUV was properly equipped to tow the load,  4 wheel disk brakes, factory class 3 receiver, weight distributing hitch, trailer brakes, safety chains.  Neither speed nor sudden movement were a problem.  Just had too little weight on the front of the trailer.  Nobody hurt, just bent metal ($10K).

[mpace6a]

The later 2nd gen rams with a cummins had better transmissions, particularly the 6spd, and 4wd has solid axles front and rear.

[xjrev10]

These pipe dream threads are fun....

 

Check out the J20 in the "your other projects" section. That's a jeep truck tow rig.

 

Towing in ND is one thing, towing in CO is another. For 10k, you could find a reg cab cummins 12v-24v with a manual trans and 4 wheel drive, rebuild the front end and buy a trailer. There's gotta be a few old welder trucks in ND that have been up for sale..

 

Bottom line is a MJ does not make a good tow rig. It's been stated on here till everyone is blue in the face.

[carnuck]

It's definitely not a good vehicle to tow with in bad weather. I towed an '82 Eagle SX4 from nearly the CA border to Seattle at 55-70 mph (over 55 wasn't allowed in Oregon on I-5) and the only casualty was the auto trans (which is getting changed out very soon), but that was because the cooler in the rad was plugged with gum or sealer since new and I had only 2 weeks before converted to auto. 

   A J10 or even better a J20 or M715 will give you what you need in counterbalance weight AND braking power.

 

My '73 J4000 was about 1/2 way between a J20 and an M715. D44 front and D60 full float rear (not original) This pic is me towing a '91 E350 28' box truck with 7.3L diesel and a full load of old CRT TVs.