Towing - Standard vs. Load-Leveling Suspension

[Bayerische E53]

Originally Posted by digdesign

It's a Trailex CT-8045, which is 14' (20' overall). It does have a tire rack in the front, but the toolbox and gas jugs are in the back. I do plan on weighing the tongue and making adjustments. This trailer has the axles mounted on rails so, if needed, I can tweak the axle location to get it just right. I bought it specifically for downsizing so that I can tow with an SUV (I was previously towing with a GMC 2500HD Durmax) I'm confident I can get the load balanced.


No. The car isn't legal for M3T, it was built long before M3T was created.

Trailex makes really nice trailers. That said, Christ, that's a REALLY small one. I didn't think you could fit any 3 series on something less than 16' long without the ass hanging off the back! Regardless, that's super compact and super cool.

I went the opposite route. I just picked up a 24' enclosed aluminum trailer myself (not Trailex, though). All in, she'll tip the scales at approx. 7,400lbs with a full load. I'm going to try towing her with the X5. First unloaded (4200-4300lbs), then with just the car, 6,900lbs, and then loaded up at 7,400lbs. There are quite a few guys on this forum towing over 6,000lbs. One has actually towed a 31', 8,900lbs Airstream over 40,000 miles without a problem (albeit with a Hensley WD/SC - a hitch which I have going on my trailer as well). That is not a typo: a 31', 8,900lbs Airstream. Anyways, that's how I'm setting up my rig - if it doesn't work I'm going to go with a 1/2 ton. If other people are doing this successfully AND SAFELY, it's at least worth a try.

A little known fact is that BMW offers an option called "increased towing capacity" that increases the X5's tow limit to 7,700lbs (this option is available on both the E53 and E70). I just found out about this and will be calling BMW tomorrow to find out what software/hardware that option actually includes. A cursory observation reveals that it's all cooling and not structurally related so the chassis should be able to handle up to 7,700lbs unmodified. You could go this route as well.

I'm just saying all this stuff so you don't worry about the load you're carrying - your expected load is not going to stress your X5.

I hear you about your E30. Very cool car.

[digdesign]

Based on the numbers we have, I should still be well under recommended limits.

With 3rd row & Load-Leveling
6614lbs Gross Weight Limit - 4700lbs Unladen Weight = 1914lbs Capacity
6614lbs Gross Weight Limit / 3858lbs Approved rear axle weight = 58% of load allowed on rear axle
58% of load capacity (1914lbs) = 1110lbs allowed over rear axle

No 3rd row & Standard Suspension
6294lbs Gross Weight Limit - 4700lbs Unladen Weight = 1594lbs load capacity
6294lbs Gross Weight Limit / 3395lbs Approved rear axle weight = 54% of load allowed on rear axle
54% of load capacity (1594lbs) = 860lbs allowed over rear axle

Does that sound about right? And is that 4700lbs unladen weight number accurate?

[digdesign]

I hear you. I know that feeling when a trailer is light on the tongue. Not fun at all. Thanks for the advice.

The limiting factor is that I want to carry a spare for the X5, since I don't want to rely on run flats if I get a puncture while towing. Which is what had me thinking that I don't want the 3rd row. For daily driving I don't mind relying on run flats. So another option is to find an X5 with the 3rd row and just carry an X5 spare on the trailer.

It all depends on what I find on the used market.

[digdesign]

I went through the same thing. I had a very basic Dively open steel trailer. Bought it new for about $2300, then sold it 2 years later for $900. I bought my Trailex used for $4500 and I don't think it'll lose much of it's value as long as I take care of it. Their values seem to bottom out in the $4000-4500 range.

You should be in great shape with that trailer. From what I've seen, enclosed aluminum trailers hold their value very well. Who built it?

[Bayerische E53]

Originally Posted by digdesign

I went through the same thing. I had a very basic Dively open steel trailer. Bought it new for about $2300, then sold it 2 years later for $900. I bought my Trailex used for $4500 and I don't think it'll lose much of it's value as long as I take care of it. Their values seem to bottom out in the $4000-4500 range.

You should be in great shape with that trailer. From what I've seen, enclosed aluminum trailers hold their value very well. Who built it?

Yup, you hit the nail on the head.

inTech is building the trailer. Similar in concept to those below but with some personal additions/omissions (i.e. in-floor winch, tire racks, corrugated aluminum floor, and some other stuff):

inTech Aluminum Trailers for Sale | RPM Trailer Sales

Aluminum Trailers

[digdesign]

That looks sweet. I wish I had the space for an enclosed. Some day.
What are you hauling?

[Bayerische E53]

Originally Posted by digdesign

That looks sweet. I wish I had the space for an enclosed. Some day.
What are you hauling?

Yeah, storage for those things ain't easy. And, honestly, neither is the maintenance. Although aluminum trailers are supposedly pretty "maintenance free," when you buy something like that, you're really going to want to care for it. I'd give your Trailex the same attention to detail (but it just wouldn't take as long because it's smaller and simpler). I'm sure you know what I mean as I bet you care for yours. Aluminum trailers aren't "buy it and forget it" items regardless of the fact that many people treat them as such. I'm not really looking forward to week-long detailing/maintenance sessions.

I'm hauling an E46 325Ci (i.e. 32Slow) track-rat-dog-pig-thing. But I love her. She was my first BMW.

[digdesign]

I'm sure it's a hoot. The rattier the better in my opinion. As they say.. It's more fun to drive a slow car fast than a fast car slow.

[Bayerische E53]

Originally Posted by digdesign

I'm sure it's a hoot. The rattier the better in my opinion. As they say.. It's more fun to drive a slow car fast than a fast car slow.

You're 100% correct. I dabbled with the idea of making her beautiful but decided I would be too scared of scratching her to enjoy her. So she's beat but I'm happy with that. For that very reason, I'd be too afraid to drive something like your E30.

I'm actually thinking of picking up a SpecE30 to thrash around in and run SpecE30 and/or Chump/LeMons; would serve as a nice and cheap backup car.

You're absolutely right that driving slow cars fast is more fun than driving fast cars slow. Here's an example (well, two):

There's a guy out of NJ that has a red E30 LeMons car that he brings out to tons of DEs. She's so damn beat - call her "The Red Barron." I've had a ride (passenger) in it before and it's just about the funnest thing I've ever been in. WHAT A BALL. I'm absolutely convinced that the easiest way to laugh your ass off on the track is to drive a LeMons car at the absolute limit. It's inexplicably fun.

Another interesting car I was a passenger in was a 2002ti that I rode in last December at VIR. I use the adjective "interesting" rather than "fun" because I don't think "fun" accurately describes the sensation you feel when you exit T10 'round about 90mph in a dedicated 4-wheel-slide in a 2000lbs sardine can without any driver aids.

[m3irish]

Interesting question on the load leveling suspension. I have the std suspension and tow ~5000lbs between the Aluma open trailer, race car, and supporting items. Rear end sag didn't seem too bad all loaded up. The inner tire wear was higher than I would have liked with equipment in the back of the car and ~500lbs on the tongue. My guess is the self leveling suspension will bring ride height back to where it needs to be and therefor the alignment as well. I am going to have the rear camber set closer to -1 deg and ease up on the toe to help with towing. Makes me wish I had spent the coin on the load leveling suspension.

All of that aside my X5d tows the rig like a champ.

Cheers,
Rob