Does anyone tow with BMW X5 Hybrid (Xdrive40e)?

[BayouBiker]

If we stick to the facts, we have the SAE test result showing they have sway control issues with more than about 550 lbs of tongue and over steer when you put more than about 700 lb of tongue on them. They have hitches that roughly match those numbers. We have a vehicle tuned for performance touring which is physics wise consistent with the SAE test results, we have copious brochures and a long history of brand identification, we have insurance actuarial tables for BMWs towing and not towing and we have BMW, people who know their vehicles 100 times better than any internet troll setting numbers consistent will all of the facts I just provided. Then we have numerous people reporting sway and over steer when exceeding 60 mph towing trailers close to the BMW set limits. Those are the facts.

On your side of the argument we have nothing but innuendo and a driver who won't dare exceed 62 mph. bono is perhaps the best evidence we have than an X5 should not pull a 7300 lb trailer. You could provide an article demonstrating performance at 65mph, or insurance experience with large trailers or a BMW technical paper on towing large trailers. You could show why the numerous other X5 owners on this forum experienced over steer and sway with 5000-6500 lbs of trailer.

Curiously you bring no data to support your position.

We didn't sell my wife's SUV, she totaled it. It was a nice vehicle, much more pleasant to drive the the truck. I won't mention what we replaced it with, it wasn't the truck. I don't like the truck much but it gets the job done.

Look if you remove the rear sway controls, add a bit of negative camber to the rear, positive to the front, deflate the front tires about 3 psi, put the rear at near max pressure, and use a propride hitch, the X5 will do a great job towing 7000+ lbs, but when not towing it will handle a bit like ... a truck. Go figure.

There is a special word for those of you who think they can outsmart physics.

[HappyHapgood]

When I think of “driving stability” I think about speed through a slalom course, or braking distance during an evasive maneuver and staying in a lane.

Which STOCK vehicle would perform better towing a 6,000 lb airstream with properly set up wight distributing hitch?

A. BMW X5 engine doesn’t matter, just pick any.
B. Ford F-150. Ditto on engine. Apples to apples let’s just say it should be 4 wheel drive.

2020 or 2015 shouldn’t really matter either.

I’m curious.

[BayouBiker]

With a 6000 lb trailer the X5 would certainly perform best. Using a 7500-8000 lb trailer would be a different story.

[jcl]

Originally Posted by BayouBiker

If we stick to the facts, we have the SAE test result showing they have sway control issues with more than about 550 lbs of tongue and over steer when you put more than about 700 lb of tongue on them. They have hitches that roughly match those numbers.

(Rant snipped)

I don’t have a copy of the SAE test results for this specific vehicle. If you do, please post them. I assume they use the SAE’s problematic FALR targets, since BMW don’t recommend WD settings. Did they even use WD? Did they reinforce the hitch receiver to handle WD torques? Did they just tow on the ball?

There is one X5 hitch design for each generation, it doesn’t vary with models, or tow ratings.

If you want to quote internet posters who note stability issues, then please provide setup details. I am not aware of handling issues being reported with properly set up combinations. We know From people who do this professionally that most vehicles are not set up correctly. It would be absurd to blame a vehicle without validating the setup first.

[BayouBiker]

The SAE test result data is proprietary. Non-disclosure agreements prevent sharing specific results.

The X5 has issues with sway stability and over steer when towing medium and larger trailers. I have yet to see any objective data to dispute this. Real experience must account for the full cross section of actual set-up otherwise you are cherry picking to support a specific prejudice.

[jcl]

Originally Posted by BayouBiker

Curiously you bring no data to support your position.

Originally Posted by BayouBiker

The SAE test result data is proprietary. Non-disclosure agreements prevent sharing specific results.

Curious indeed.

[BayouBiker]

Nice projection. The specific individual test data is proprietary but the summary results are public domain. In the US market, they become the published towing limits. Therefore despite your protest, the safe towing limit is evidence that any particular configuration is unable to pass one or more of the SAE J2807 tests with more than the published load. These limits are corroborated by reported experience and more. You have nothing objective to contradict the SAE results.

[jcl]

You didn’t answer the questions posed in post #124. We have no data to be able to evaluate the SAE results.

[BayouBiker]

The final load limits are the result data. Since we have no contradicting information, and plenty of corroborating reports, there is nothing to evaluate the results against and no rationale to dispute the limits. Do you have data that supports your hypothesis the X5 would perform better in the SAE tests with significant WD and a more rigid receiver? Do you know something the BMW engineers do not? If so come forward with the evidence.

[bono]

I admire Jeff's patience. This is a hopeless case... I got it, some people cannot understand that some manufacturers do not care about towing capacity numbers on some markets. This may be difficult to digest for somebody from the US, where truck manufacturers are in a race to put higher and higher towing capacity numbers. But still...

[jcl]

Originally Posted by BayouBiker

The final load limits are the result data. Since we have no contradicting information, and plenty of corroborating reports, there is nothing to evaluate the results against and no rationale to dispute the limits. Do you have data that supports your hypothesis the X5 would perform better in the SAE tests with significant WD and a more rigid receiver? Do you know something the BMW engineers do not? If so come forward with the evidence.

You are asking us to blindly accept incomplete data without context. That isn’t sound engineering.

Since BMW don’t recommend WD or supply a hitch receiver designed for WD, we can hypothesize that any SAE tests were conducted without WD installed, or if it was installed, with artificially low FALR. Let’s go with no WD, since they wouldn’t modify the receiver. Now, what do you think happens to that effective capability when you use WD and a proper hitch receiver?

You should stop trying to blame the BMW engineers, who have no training, experience with, or history to draw on related to WD equipment, simply because they are located in Germany.

If you want to know about towing with the X5 you should talk to CanAm. The first large Airstream matched to an X5 that I know about was poster withidl, 31 Classic with modifications including an on-board Onan generator, 19 years ago. Lots of details on this forum. CanAm set it up. Withidl was an engineer too. He gave up here because of being told “you can’t tow with that!”

I was interested in talking with CanAm. I drove there. Learned lots. Withidl travelled from Texas. Such is CanAm’s reputation. They advise on optimal setup. You don’t believe in their approach. Can’t help you with that. Maybe you should talk to them if you are going to post about them so much. Especially if you are going to continue to criticize their approach

[HappyHapgood]

Hmmmm. Food for thought. So you are suggesting, because SAE has done some testing, that manufacturers put max tow ratings on their vehicles that are solely the result of the SAE tests?

Back to the question about stability. If we believe that manufacturers use SAE results to cap their tow ratings, then in theory the stability of an F250 towing its max rating (maybe 17,000 lbs?) should handle the same as an X5 towing it’s max (7,200)? Call me skeptical. Or take it a step farther... the F250 towing NOTHING will likely not be as “stable” as an X5 on slalom and evasive braking, even if the X5 is towing a 2000 lb trailer (one with brakes and reasonably low CG). So how does the SAE test really work?

[BayouBiker]

jcl, summary data is in the public domain and it has been provided but it contradicts your prejudice so you nit pick it till you can convince yourself it is incorrect. I have detailed data and models and multiple accounts of actual on road experience all confirming the summary data. You have read their reports and accounts of on road experience also.

You complain about each aspect of the information provided and hypocritically dismiss it all. You offer no data, none at all to support your position and then ironically you describe my position as unscientific. The scientific method is to make a hypothesis and then with counter evidence, prove it wrong. In the process, if supporting evidence comes to light the strength of the hypothesis is improved. Your job is not to complain I don't have enough evidence to satisfy your hardened prejudice, it is to bring forward contradicting evidence and prove my hypothesis wrong. You have failed in your task. You are the person practicing unsound engineering by stubbornly clinging to your prejudice without any supporting evidence.

It is a well known principle of suspension and handling that if a vehicle-trailer system experiences over steer with no WD, the over steer will be worse as tension is added. This fact is not in dispute. No sane skilled engineer would argue this point.

The folks at Can-Am monitor and comment here from time to time, I have never had occasion to dispute their technical statements, and I trust their technical judgement. They do have a product to sell, I get that, so they don't have any incentive to get into a loosing technical argument. I suspect they will stay silent, but even if they don't, I don't expect we will disagree on any technical point. My argument is not with Can-Am, it is with the customers who don't understand the product they purchased. I don't disagree with Can-Am's approach or their technical advice, particularly on set-up for any vehicle capable of towing the particular trailer. For that task, I think they are spot on with it. As far as I know, I set my system up exactly the way they describe, and completely agree with the their complaints of alternate set-up.

I get also that your bias requires you to trash the BMW engineers. I give them far more credit than you do.

[BayouBiker]

Originally Posted by HappyHapgood

Hmmmm. Food for thought. So you are suggesting, because SAE has done some testing, that manufacturers put max tow ratings on their vehicles that are solely the result of the SAE tests?

No, they also consider brand image and customer target for that particular vehicle. They add additional performance parameters including things like in vehicle comfort measures, suspension travel limits, etc. This is why one must understand the particular vehicle and the limiting factors that went into the final limit. In the case of the X5, it is handling stability. In the case of the Chrysler 300 it is suspension travel and perceived passenger comfort.

Back to the question about stability. If we believe that manufacturers use SAE results to cap their tow ratings, then in theory the stability of an F250 towing its max rating (maybe 17,000 lbs?) should handle the same as an X5 towing it’s max (7,200)? Call me skeptical. Or take it a step farther... the F250 towing NOTHING will likely not be as “stable” as an X5 on slalom and evasive braking, even if the X5 is towing a 2000 lb trailer (one with brakes and reasonably low CG). So how does the SAE test really work?

No, handling performance share some similarities with stability but they are not the same. So an F250 at max will be stable, it won't go out of control in test maneuvers but it will continue to handle poorly. The X5 will continue to handle well, but if you exceed test parameters, it will experience sway or over steer and go out of control. An F250 is rated to tow 17,000 but you could not safely get that on the hitch ball, you would have to use a goose neck or 5th wheel. Stability for a 5th wheel is a different ball game.

An F250 necessarily handles very poorly and is unstable with a light load in tests that exceed highway conditions. It has severe under steer and will plow out of a slalom. Heavy tow vehicles have suspension that is biased for heavy loads so they are stable and safe with load. That reality burdens them with poor handling performance. That performance reality stays with them for all conditions because it is inherent.

Performance vehicles are the same way, they will retain their basic characteristics when towing. However, since they are not set up to tow, they, while continuing to perform well, have baked in stability issues they cannot shake. They will have over steer and sway instabilities you simply cannot even partially fix without detuning and removing the performance characteristics. But then they will curiously handle more like a truck. Go figure, you can't have your cake and eat it too.

[jcl]

Originally Posted by BayouBiker

The folks at Can-Am monitor and comment here from time to time, I have never had occasion to dispute their technical statements, and I trust their technical judgement. They do have a product to sell, I get that, so they don't have any incentive to get into a loosing technical argument. I suspect they will stay silent, but even if they don't, I don't expect we will disagree on any technical point. My argument is not with Can-Am, it is with the customers who don't understand the product they purchased. I don't disagree with Can-Am's approach or their technical advice, particularly on set-up for any vehicle capable of towing the particular trailer. For that task, I think they are spot on with it. As far as I know, I set my system up exactly the way they describe, and completely agree with the their complaints of alternate set-up.

I get also that your bias requires you to trash the BMW engineers. I give them far more credit than you do.

If CanAm recommend the X5 as a great towing vehicle, and consider safety in all of their setups, and test all their setups, and have endorsed at least one 31 AS matched to an earlier, lighter X5, and have set up/tested/written about many Euro SUVs for larger Airstreams, and you don’t disagree with their approach or technical advice, then why are you still arguing?

It is an aside, but I don’t trash BMW engineers. Their competence is why I purchased six later model BMWs. I also worked on many more than that. Don’t conflate criticism of a company’s local marketers with lack of confidence in their design engineers.

The bias you are seeing is a reluctance to accept theoretical results over real world experience when they disagree. The two need to be reconciled. Use your oft stated concern about oversteer as an example. It is entirely possible for the propensity for oversteer to increase, while still coming nowhere close to a real world concern. Test track and slalom results count more than models in that reconciliation effort. And through all of this, there are generally two groups of people. Very roughly, they can be divided into those that don’t believe you can tow a larger trailer safely with a Euro SUV, and those who are doing it. So it goes. It isn’t a new situation, this discussion has been going on since shortly after BMW invented this product class in 1999. It also parallels discussions about safely towing with certain minivans, sedans, and so on.

[BayouBiker]

The X5 is a great towing vehicle, but that is a subjective description. It is apple pie and motherhood to consider safety, again subjective, as is endorsing various set-up without providing stability limits and safe speeds.

Several X5 owners have reported their experience here. You accept subjective statements from those that confirm your position and explain away those who contradict it even when they offer objective data including speed and road condition. You even project. Take the case of bono who reports solid handling at 55-60 mph but thinks people are crazy for towing at 65+. Then you go right ahead and use his experience to project and imply that an X5 can safely tow a large heavy trailer at the common US speeds of 65-70 mph with no stability issues.

My models are consistent with all the subjective experience being reported. There is no disagreement with the models (which show good stability and performance at 45 mph) and all real world experience reported. Since these real world examples did not provide scenarios where their experience was stable but the model indicates instability, they corroborate the model perfectly.

It's hard to measure the point where real world concern exists for over steer. SAE seem to define it at the point of neutral steering response for 0.3 g cornering which exceeds all road design parameters. Stunt drivers can easily manage some modest over steer, but insurance data indicates the average driver does not. Since the audience on this forum seems more like the average driver I speak to that.

[bono]

Hey BayouBiker,

Can you stop referring to what I say about towing at 65+ mph and X5 towing performance? I think it is crazy to tow 65+ mph, in particular, with trucks due to their poor handling and poor braking. X5 would handle better at 65+ than truck, but it is not wise to have a few tons in the back and go 65+.

I explained that to you already, but you still conveniently join these two things.

[ROBERT CROSS]

No-payload fan-men unite...defend your choices.

Bob
🇺🇸

[EDWARD W LUI]

This post seems a bit dated but here goes:

Now that the x5 45e is out (I have on order), I was thinking about towing the Flying Cloud 25FB which is 7200 lbs capacity with factory installed hitch. As long as I don't overload the FC 25FB, I should be fine. However....the tongue weight with batteries/propane tank on that trailer is 837 lbs and I believe the hitch weight for the X5 is somewhere around 600 lbs. The Airstream Dealer said that if the X5 is used with a weight distribution hitch, that 600 lbs may be higher. Can anybody confirm? I may have to squeeze my family of 5 in a Basecamp if this doesn't work! LOL

[jcl]

Originally Posted by EDWARD W LUI

This post seems a bit dated but here goes:

Now that the x5 45e is out (I have on order), I was thinking about towing the Flying Cloud 25FB which is 7200 lbs capacity with factory installed hitch. As long as I don't overload the FC 25FB, I should be fine. However....the tongue weight with batteries/propane tank on that trailer is 837 lbs and I believe the hitch weight for the X5 is somewhere around 600 lbs. The Airstream Dealer said that if the X5 is used with a weight distribution hitch, that 600 lbs may be higher. Can anybody confirm? I may have to squeeze my family of 5 in a Basecamp if this doesn't work! LOL

You need a WD hitch, to manage axle loads. That doesn't help with the hitch load. Also, be cautious about the published tongue weight for the 25, as some tend to load up the front storage and push it higher.

Several versions of BMW receivers are not suitable for WD equipment. Not sure about the one you have on order. If it has a detachable tow ball, those are usually the problematic ones. If it is a traditional receiver, you are better off. You may want to have the receiver reinforced. Many have done it. The vehicle is strong, but the standard receiver is attached such that it doesn't necessarily do a good job of transferring torque loads to the vehicle unibody. Bono, who posted above, has done this himself. Others have used CanAm. Lots of posts available.

I towed with two BMW X models, but earlier versions. I am not current on this year's X5 models. I am confident, however, that it will tow very well, as mine did.

Jeff