[Megs335]

Hey guys, I remember seeing a post awhile back in one of the threads about towing/hitches of someone who did a rear helper bag install with onboard compressor. I've google'ed and searched here to no avail, does anyone happen to recall the gentlemen's username? I'm driving to california at the end of the month and would love to pop a quick set of helper's in before the drive out. Of course neither Airlift or Firestone have a helper bag listed in the catalog as it was just a universal one used IIRC. Thanks!

[charlie fairmont]

I think it was called "this is why I sold my truck"

[rulonger]

Originally Posted by Megs335

Hey guys, I remember seeing a post awhile back in one of the threads about towing/hitches of someone who did a rear helper bag install with onboard compressor. I've google'ed and searched here to no avail, does anyone happen to recall the gentlemen's username? I'm driving to california at the end of the month and would love to pop a quick set of helper's in before the drive out. Of course neither Airlift or Firestone have a helper bag listed in the catalog as it was just a universal one used IIRC. Thanks!

http://www.e90post.com/forums/showthread.php?t=1262117

User name is Quikdzl

[Megs335]

Ah ha! You guys rock! I was trying every key word I thought would be in the post and kept getting squat pulled up in searches. I'll post up some install pics .

[QUIKDZL]

Yeah, it was me. Digitaldav did it, too. Airlift kit is PN 46144. It has 3x9 springs. You'll also need spacers 09110 and 09444. Run springs at 5 psi at all times, and 35 psi when towing.

If you want the wireless digital compressor kit, the PN is 25870.

[Thecastle]

Assuming this is for a sedan.

Even with helper bags in the rear, you have to watch the tongue weight and make sure you don’t exceed the gross vehicle weight. Since the 335d has no official towing specs with a class 2 hitch, let’s say 3500lbs trailer and 350lbs tongue weight. When towing you don’t want to exceed the weight capacity of the car or tires. My 335 lists maximum cargo as 1000lbs, so if you stick 350lbs of,tongue weight on that leaves you 650lbs for you, passengers, cargo and fuel. Or in other words, you and 1 person in the car while towing, plus some stuff and inflate your rear tires probably to the 100mph inflation pressure.

Towing level helps.

Towing is totally doable on a 335d. It’s the tongue weight you have to watch. If you get a class iii weight distribution hitch you could go further.

[QUIKDZL]

Yeah--for sedans. I based my decisions on the European towing specs for this car. If I remember correctly, they were 4000 pounds with 200 pounds tongue weight. I bought the Execuhitch, which is completely hidden and, because it replaces the bumper subframe with its hitch mount, exceeds the vehicle's towing specs. I installed a back-up camera from Bimmerretrofit and installed the hitch.

The E90's coils are progressive, meaning the upper few inches of the spring length are thinner and have a lower spring rate than the lower coils. A 200-pound tongue weight will cause the rear end to sag a couple of inches. I added the AirLift bladders and automatic compressor to prevent this. I have a lightweight PWC trailer with a tongue weight of about 60 pounds, so I set the spring pressure to 15 psi to remain level. My twelve-foot single-axle box trailer has electric brakes with a trailer-mounted brake controller and can easily put 400 pounds on the tongue. I simply inflate the bags to 35 psi and rock on level and steady (and fast).

And yes, you do not want to exceed the GVWR of the vehicle or the capacity of the tires.

[digitaldav]

So far very happy with my new tow vehicle.