New OEM Hitch Specs R a "Gotcha"!

[DSAviate]

Just bought an E53 OEM hitch from the dealer (~$495 with harness for the 100 lbs box). (Westfalia No. 303 169 600 105, and BMW dealer part no. 71-60-0-009-711) Real beefy chunk of steel, looks like it has one coat of black paint and can't wait to start rusting.

Anyhow, it looks and attaches just like all the other OEM hitches shown here on the forum. I'd like to think I've read most everything here on E53 hitches.

Take a good look at the placard (attached) that comes with the new hitch made by "Westfalia American Hitch Inc." The ball mount limitations are identical to those shown in the installation instructions.

No chance of using the riser mount I'd like to. According to the OEM hitch docs, not even a straight shank mount is permitted. The mount must drop as specified.

Spoke to a "hitch rep" at the manufacturing company, but in essence all he's said is stick with the schematic limitations. (I don't think previous OEM hitch installation instructions showed these limitations.)

So, here's the problem. Where can I find a class IV (6000/600) 2" ball mount that drops 4" and has a shank length of NO MORE THAN 8"??

It may be out there, . . . but I certainly have looked (and had several vendors looking) and found nothing!

According to these limitations, you can't attach so much as a bike rack unless it has the required drop and short shank length.

What am I missing here? Somebody please make a total fool of me, show me what I'm missreading, and I'll get an appropriate (LEGAL) mount and be on with life.

The pulling is more enjoyable when you KNOW you're legal.

- M54 Lover

[admranger]

First, make sure that whoever you are talking about getting a shank has this pic. I'm not certain that the drop for a shank is measured as pictured. To me it looks like a 1.5 to 2 inch drop as pictured (I thought drop was top of shank to top of ball...).

I've had good luck w/etrailer.com, but I don't know if they have what you want.

Seems odd that it requires a drop range so tightly spec'd. I have the drop on my dually hitch adjusted so that the loaded trailer is level to equally distribute the weight on both axles.

Thanks for posting this though. Great info to have for those of us contemplating a hitch in our future.

[JCL]

The hitch was designed for that particular limitation of drop and extension. Anything more than that would apply a higher bending moment that the unibody attachment points are designed for. You can take that chance if you want, but I wouldn't recommend it. The limitation hasn't changed with the new hitch manufacturer, those are the same dimensions in my 2003 installation instructions, and the same label that was supplied by BMW with my hitch with instructions to attach it to the vehicle.

I bought my ball mount from my dealer when I bought my hitch. It was within the specs shown on the schematic. There are threads about posters who have purchased non-OEM ball mounts and had rattles. You can always shim them, but I figured it was easier to just buy the ($$$) BMW part as it fit snugly.

I don't agree that you necessarily want a Class IV mount. Most will be labelled Class III at 6000 lbs/600 lbs tongue weight. Class III isn't a precise specification, there are 5000 lb hitches and 6000 lb hitches, all labelled Class III. Some Class IV hitches are labelled 6000 lbs, others 7500 lbs, and others 10,000 lbs. If a Class III ball mount is labelled 6000 lbs, that would be sufficient.

It is a side point, but the spec doesn't cover bike racks. The hitch is designed for the load to be applied at the hitch ball. If you mount a bike rack, you need to figure out the new CoG, and weight. Then figure out if you are applying a greater bending moment than the hitch was designed for. Most bike racks are very light and it won't be an issue, but it is worth checking.

Good luck.

Jeff

[admranger]

Originally Posted by JCL

The hitch was designed for that particular limitation of drop and extension. Anything more than that would apply a higher bending moment that the unibody attachment points are designed for. You can take that chance if you want, but I wouldn't recommend it. The limitation hasn't changed with the new hitch manufacturer, those are the same dimensions in my 2003 installation instructions, and the same label that was supplied by BMW with my hitch with instructions to attach it to the vehicle.

I bought my ball mount from my dealer when I bought my hitch. It was within the specs shown on the schematic. There are threads about posters who have purchased non-OEM ball mounts and had rattles. You can always shim them, but I figured it was easier to just buy the ($$$) BMW part as it fit snugly.

I don't agree that you necessarily want a Class IV mount. Most will be labelled Class III at 6000 lbs/600 lbs tongue weight. Class III isn't a precise specification, there are 5000 lb hitches and 6000 lb hitches, all labelled Class III. Some Class IV hitches are labelled 6000 lbs, others 7500 lbs, and others 10,000 lbs. If a Class III ball mount is labelled 6000 lbs, that would be sufficient.

It is a side point, but the spec doesn't cover bike racks. The hitch is designed for the load to be applied at the hitch ball. If you mount a bike rack, you need to figure out the new CoG, and weight. Then figure out if you are applying a greater bending moment than the hitch was designed for. Most bike racks are very light and it won't be an issue, but it is worth checking.

Good luck.

Jeff

Great info Jeff! I had no idea BMW actually had a ball mount for sale. No doubt it was $$$. That should be painfully obvious to us all by now!

[JCL]

Just looked it up. In 2003, the BMW ball mount was part number 72-11-0-009-120, labelled as E53 Ball. It was $79.50 CDN at the time, probably twice what a trailer store would have charged. I don't know if that part number has changed up or not.

On my original invoice, the hitch is the same part number as listed by the OP.

[upallnight]

Originally Posted by JCL

The hitch was designed for that particular limitation of drop and extension. Anything more than that would apply a higher bending moment that the unibody attachment points are designed for. You can take that chance if you want, but I wouldn't recommend it. The limitation hasn't changed with the new hitch manufacturer, those are the same dimensions in my 2003 installation instructions, and the same label that was supplied by BMW with my hitch with instructions to attach it to the vehicle.

I bought my ball mount from my dealer when I bought my hitch. It was within the specs shown on the schematic. There are threads about posters who have purchased non-OEM ball mounts and had rattles. You can always shim them, but I figured it was easier to just buy the ($$$) BMW part as it fit snugly.

I don't agree that you necessarily want a Class IV mount. Most will be labelled Class III at 6000 lbs/600 lbs tongue weight. Class III isn't a precise specification, there are 5000 lb hitches and 6000 lb hitches, all labelled Class III. Some Class IV hitches are labelled 6000 lbs, others 7500 lbs, and others 10,000 lbs. If a Class III ball mount is labelled 6000 lbs, that would be sufficient.

It is a side point, but the spec doesn't cover bike racks. The hitch is designed for the load to be applied at the hitch ball. If you mount a bike rack, you need to figure out the new CoG, and weight. Then figure out if you are applying a greater bending moment than the hitch was designed for. Most bike racks are very light and it won't be an issue, but it is worth checking.

Good luck.

Jeff

Bikes shouldn't be a problem I carry my Felt and Cervelo on a Saris bike carrier attach to my OEM hitch, not unless your ideal of a bike is a HD Electra glide.

[JCL]

Originally Posted by upallnight

Bikes shouldn't be a problem I carry my Felt and Cervelo on a Saris bike carrier attach to my OEM hitch, not unless your ideal of a bike is a HD Electra glide.

Four-bike holders loaded with full suspension mountain bikes are typically over the limit due to the bending moment resulting from the rear offset over and above the 8" spec. Cargo trays are nearly always over the limit.

I put my Cervelo R5 and my wife's R3 on the roof in fork mounts, with two wheel holders. Heading out this weekend.

[UCrewX5]

The BMW part number is 72110009120



Comes with a 2" ball.

$47.48 from ECS Tuning - Home Page > Search > 72110009120 > ES#185512 Designed for use with the X5 trailer hitch kit. - ECS Tuning Inc

[N S]

Originally Posted by DSAviate

Just bought an E53 OEM hitch from the dealer (~$495 with harness for the 100 lbs box). (Westfalia No. 303 169 600 105, and BMW dealer part no. 71-60-0-009-711) Real beefy chunk of steel, looks like it has one coat of black paint and can't wait to start rusting.

Anyhow, it looks and attaches just like all the other OEM hitches shown here on the forum. I'd like to think I've read most everything here on E53 hitches.

Take a good look at the placard (attached) that comes with the new hitch made by "Westfalia American Hitch Inc." The ball mount limitations are identical to those shown in the installation instructions.

No chance of using the riser mount I'd like to. According to the OEM hitch docs, not even a straight shank mount is permitted. The mount must drop as specified.

Spoke to a "hitch rep" at the manufacturing company, but in essence all he's said is stick with the schematic limitations. (I don't think previous OEM hitch installation instructions showed these limitations.)

So, here's the problem. Where can I find a class IV (6000/600) 2" ball mount that drops 4" and has a shank length of NO MORE THAN 8"??

It may be out there, . . . but I certainly have looked (and had several vendors looking) and found nothing!

According to these limitations, you can't attach so much as a bike rack unless it has the required drop and short shank length.

What am I missing here? Somebody please make a total fool of me, show me what I'm missreading, and I'll get an appropriate (LEGAL) mount and be on with life.

The pulling is more enjoyable when you KNOW you're legal.

- M54 Lover

Good to know, I just ordered mhy OEM hitch from Bloomfield BMW - I'm assuming I'll receive the same thing. Sounds like I'll do a light sand, primer, and a couple of coats of paint prior to installing.

[DSAviate]

Hey Guys - Thanks for the info.

The drop is measured from the top of the bar of the shank to the top of the plate that supports the ball. But, the OEM hitch requirements show a 4" minimum drop from the top of the receiver to the top of the plate supporting the ball. The receiver square tubing is 1/4" thick in this area. So, I will have to find a mount with at least 3 3/4" drop. So far I've only found increments at 3 1/2" and 4". The shortest shank lengths I've found so far are 8 1/2".

The dealer had originally told me they don't have a mount. Based on your replies here I inquired again. Picked up the mount today just to have it in hand (would like to find a SS or solid aluminum mount). Noticed when I got home that it was for the E70 . . . bonehead!!

Plan to pickup the E53 mount on Monday. If it isn't w/i hitch limitations, I'll have a meltdown at the dealership in the chief cheese's office.

Jeff, you're right that I don't need a certain class, but rather the 6000/600 rating on all components, car, hitch, mount, ball, & coupler.

Just saw the posting of an easy OEM hitch installation today. Will let you guys know how mine goes.

BTW, got an '01, 5 spd MT, Silver/Black. Will change all the oils in the next few days with the following unless you towing guys recommend something else:

Engine - LubroMoly 5w30
MT - OEM Gear Oil, 5 Liter - MTF-LT3 - For Manual Transmissions from BavAuto (pricey), or Castrol Synthetic Gear Oil 75w90, haven't decided
Transfer Case - Lubro-Moly or Castrol Gear Oil 75w90, Undecided
Frn & Rr Diff - Lubro-Moly or Castrol Gear Oil 75w90, Undecided

Can't wait to start pulling with her.

- Darrell