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View Full Version : Moving a bridgeport mill with XJ cherokee



beatupjeep
03-06-2016, 02:09 PM
I have a small machine shop at home and occasionally need to transport equipment I buy to my house. The heaviest I've moved so far is a 5000 lb cnc lathe. To do that I rented a 3/4 ton pickup and trailer, both of which had far beyond the required cargo/towing capacities to do the job.

But my latest purchase was more like 2000lbs, basically bridgeport mill size and weight. Renting the pickup and a trailer is expensive and a huge hassle since I have to drive another 2 hours or so just to pick up an drop off the equipment at two different rental places, plus, if my whole transport process went over by a day or so, it was very expensive to pay for an entire other day of pickup+trailer. And the loading and unloading process can take a long time, so rushing against the clock sucks. So I wanted to see if I could get the job done safely and legally with my poor old jeep.

The machine in question is not actually a bridgeport mill. But has practically the identical footprint, height, and weight as a bridgeport mill, so I believe this experience directly translates to moving one. I found lots of XJ towing stories on the net, varying wildly from "2000 lbs is terrifying" to "I just towed 6000+ lbs through mountain passes no problem" etc.. so it was basically impossible to get an idea how my XJ would do. Especially since performance and safety can be affected drastically by proper tongue weight and loading, details of which are not really ever in those stories. Not to mention driver tolerance and skill level.

My XJ:

1989 Cherokee 4 door 4wd
Peugeot manual tranny
Rear diff is the lowest (numerically) of all, I think the 3.08?
I have a lock rite locker in the back.
Engine 200k miles, unknown last rebuild if ever
Tires: basically new General Grabber AT3s, slightly bigger than stock (LT235/75 R15), inflated to 35 psi cold
Shocks and rear springs have maybe 30k miles on them, and are stock replacements. Springs are standard rate.
Hitch is a Class III uhaul hitch I got from the junkyard, properly bolted and torqued with plates to the frame. The ball mount was a 6000 lb 2" I got from pepboys for $22 (pin+mount+ball) w/ 25% off coupon.
Brakes are stock disc front drum rear.

My Jeep runs 0-60 in about 12 seconds, which is several seconds slower than new. So its definitely not putting out full power.

The trailer:

I chose the uhaul 5x9 single axle with a cargo capacity of 1910lbs and an empty weight of 990lbs, for $19 a day. The machine should basically max out the cargo capacity within 100lbs. My XJ owners manual says tongue weights above 350lbs need a weight distributing hitch, which can't be used on uhaul trailers (both per their policy, and they physically have nowhere to attach). For 10% tongue weight, fully loaded, it would be about 290lbs.

Uhaul also has a 6x12 2 axle trailer trailer, but it weighs about 800 lbs more and I think would have made everything worse because of the extra weight. Plus, I couldnt have 1900lbs of cargo in it without exceeding the 350lb tongue weight for the XJ. Although it does have brakes.

Note that there are a ton of different "5x9" utility trailers at a given uhaul. Who knows what you'll find. Some have cargo capacities of only 1700lbs. You cant trust the website, gotta go there and see whats what. Also, the 5x9 trailers do NOT have brakes!

First thing I noticed driving with the empty trailer was how much it bangs around. Theres only about 40lbs of tongue weight so its just hopping around on the ball. I could feel the drop in performance already, but it wasnt horrible.

Loading:

The machine was put into the trailer with a forklift, but there are a zillion ways to get a bridgeport into a trailer. Beyond the scope of this etc.etc.. Anyways, to get the tongue weight right I used a bathroom scale and inched the machine foward with a porta-power, which is MUCH more convenient and handy than a come along for in-trailer movement of a machine like this. Seemed like every inch of movement towards the jeep raised toungue weight about 30 lbs, going up faster as it got closer. I eventually got tongue weight to 280lbs, then added one more inch to put it around 320lbs (couldnt weigh that as scale maxed out). This caused the back end of the jeep to sag about 3 inches! The front went up about an inch. So I backed it off an inch the other direct. So tongue weight was probably 280lbs. The front/rear sag didnt change much, still at a couple inches in the back and about 1 inch up in the front.

Driving:

90 miles, almost all freeway. Steepest grade only maybe 2.5% or so. OUtside temperature around 70F. On certain uphill stretches, the engine power would really start suffering and the temperature gauge would start going up. I pulled over once to let it cool down. It didnt get into the red, but it was going up and and I didnt want it to have a chance to get there. Other times I could easily exceed 65mph (accidentally) on what appeared to be flat ground.

I did not see any sway at all or feel any unusual trailer behavior at speeds up to 65mph (max I went). The trailer+cargo weight is only a few hundred pounds shy of the jeep weight, and you can definitely feel the jeep get jolted around if the trailer hits a bump, but its not excessive. Braking is definitely worse but not dangerous if you are paying attention like you should be when towing on the freeway in socal.


Conclusion:

If your jeep is old like mine, I would not attempt this in high heat or with lots of hills, I think overheating is pretty much guaranteed in that case. If not simply blowing a head gasket or something else. I suppose if you had to you could go MUCH slower. Or maybe if the distance is much shorter.

Now, thinking about really maxing the jeep out at 5500lbs? Almost twice this trailer weight? I could see that possibly happening, but I believe every requirement in the owners manual. Weight distributing hitch for sure, auto tranny would be much nicer for take off, and of course, an engine that is more like 90% original power instead of %60.

Overall I'm glad I did this, as it is very useful to be able to use the XJ for towing machines of this weight. I think my XJ now deserves an engine rebuild, brake upgrade, etc... for the next time I do this.

http://i.imgur.com/as4LQPdl.jpg
http://i.imgur.com/GdAmkfdl.jpg

4.3LXJ
03-06-2016, 02:16 PM
Yes, it can be done. I have towed 5500# behind mine for 680 miles through the mountains. But it sure wasn't fun. I will use the pickup next time. But if you keep a good head on your shoulders, you can do it. I am jealous by the way. You have toys I want

beatupjeep
03-06-2016, 04:21 PM
Yes, it can be done. I have towed 5500# behind mine for 680 miles through the mountains. But it sure wasn't fun. I will use the pickup next time. But if you keep a good head on your shoulders, you can do it. I am jealous by the way. You have toys I want

aha yes it was you who accomplished that feat! Heres my old thread from awhile back when I was contemplating all this, where you posted some pics of your tow setup for this I believe, good stuff:

http://mandy.muckleroy.com/showthread.php?t=18784&page=2

Now that I've done half the weight and on much easier terrain and can see that I was basically at the limit as far as being able to pull it, power wise, I'd be curious to know what shape your engine was in. Im guessing pretty good? This really makes me want to give my jeep at least a valve job and re-ring.

And I definitely see how weight distribution (or much stiffer springs like you did) would help. Only about 300 lbs of tongue weight really caused the back to compress. 600 lbs would probably hit the bump stops on stock springs. Is there a tradeoff between using stiffer springs to keep the jeep level under tongue load, or a weight distributing hitch? I would think the stiffer springs would simply have a stiffer ride. But you would be able to use those with convenient and cheap uhaul trailers (with built in brakes). While a weight distributing hitch would require renting or buying a normal utility trailer, probably without brakes.

As I mentioned about the 5x9 trailers, that are a ton of variations of trailers actually at uhaul, and the website doesnt seem to show them. For instance, at the one I went to, there was a 6x12 trailer that could take 3710 lbs of cargo! (see pic below), but other 6x12's next to it were only rated for 2670.

http://i.imgur.com/Mdbg1sql.jpg

blazer2
03-06-2016, 06:45 PM
That trailer is fine. But a lowloader would make life way easier.
The trailer drops to ground. To help load and unload. Your local equipment rental store.
May have one. I rented one for a day and it costed me
$35.00 for 4 hours to move my tool boxes. Cheaper than a tow truck.

blazer2
03-06-2016, 07:00 PM
It looked like this but a lot nicer.