Audi TV blown tires—what did I do wrong?

[ROBERT CROSS]

Get new tires.

There is no reason to have the ball so high.

Unhitch...level the AS and measure to the top of the coupler.
Adjust the hitch down so the top of the ball is the same as the top of the coupler. Hitch up and use the WD adjustment to bring the rig back to level...go the the CAT Scales to confirm.

Bob
🇺🇸

I do not see 'level' or any 'bar bend'.
Is there friction sway installed on the curbside?

[PB_NB]

I would consider Michelin Pilot Sport AS3+ or AS4 XL tires which will come in at about 2,250 lbs. capacity per tire. I was running the AS3+ tires in on my previous tow vehicle and they were exceptional in every way (a bit pricy compared to Lionharts). But long range life expectancy should help. Run them a few pounds higher in the rear when towing and you should have good luck.

[pteck]

I believe it to be at least a few things you'll want to take action on. In order of importance.

1) More WD tension
2) More rear tire pressure, I would go 5-8 psi above door sticker
3) Quality tire with sufficient load rating

There's a confluence of things going on. You have inadequate tension on the WD hitch to transfer load off the rear axle, onto the front axle and back to the trailer axles. Yes, with insufficient tension, this puts a greater load on the rear axle. But it's more subtle than that. More load on independent rear axle squats the suspension, for a performance SUV as you have, tends to cause the rear tires to toe-in. More toe-in causes the tires to scrub, even driving straight ahead, building additional heat in the tires.

The heat from toe in alignment, combined with the greater tire load, and inadequate tire pressure, is causing the tires to fail.

From your picture, I believe you'll need to adjust the hitch head one position down. Then at least 2 links on the WD chain.

[suncoasteng]

You have the wrong size rims & tyres for heavy loads. 21-in are Millennial tyres, made for looks and not for doing any work. Toss out the tyres and rims, go with a 5 lug 15 or 16-in rim and buy decent heavy load tyres. I run General Grabber 15-in passenger tyres -- rated at 2470 lb .....you can also get a 16-in LT tyre, but they are noisy, thats why I like the Grabbers, passenger tread runs smooth and quiet, and i do not run off road so I do not need an All Terrain tread.

[bibbs]

I would try to find some truck rims and tires. Or Start over and get the whole truck.

[Gsmblue]

Lots going on there and some good advice here.

What tire pressure are you running? There is a sticker on the door with the recommended pressure for the vehicle. There is a max load number and associated pressure on the tire itself too, which will be high than the door sticker. When I am towing I am usually closer to the number on the tire.

It is hard to tell from that photo as things can get distorted, but it looks like your WD bars are not doing much work. Are they under tension? Are you familiar with how to set up the WD?

[jcl]

Originally Posted by suncoasteng

You have the wrong size rims & tyres for heavy loads. 21-in are Millennial tyres, made for looks and not for doing any work. Toss out the tyres and rims, go with a 5 lug 15 or 16-in rim and buy decent heavy load tyres. I run General Grabber 15-in passenger tyres -- rated at 2470 lb .....you can also get a 16-in LT tyre, but they are noisy, thats why I like the Grabbers, passenger tread runs smooth and quiet, and i do not run off road so I do not need an All Terrain tread.

Do you really think those 15" rims would fit over the brake calipers of an Audi Q7? One could go down to the 18" that Audi offered, as long as the calipers are the same size in the base model, but those tires will squirm around more and so not be as stable when towing.

The tire size is fine. The tires are XL rated, so are fine for expected loads. I don't know that brand, but wouldn't expect much.

Start with the proper tire pressure. Check axle loads.

[aftermath]

I am with Bob. Lower the ball, connect the trailer and increase the WD tension. You want your trailer to be level (it is) but it is more important to see your TV level as well. Do check the air and the load rating of the tires you will be using. If the rating is close to the actual load make sure you air the tires up to the max mentioned on the sidewall. Probably should do this anyway with a performance tire.

[Silvr_Bullet]

Your hitch looks so very close to the TV, or maybe it’s optics?

[DMT]

X3 - I am with Bob as well. He (and other posters) know what they are talking about. Dial the hitch in to get the slight bend in the bars (assuming you have the correct size bars) with a level trailer. Put tires on the Q7 that are up to the task of carrying the load. You may need to change the rims to achieve that.

There is absolutely no reason why the Q7 cannot tow your Bambi safely and efficiently, in my opinion.

[BayouBiker]

I get that many of you have issue with off brand tires, I certainly don't buy them either, but those tires have good load capacity if they were inflated, they also have good reviews online and no history of premature failure. You all are correct there was not enough WD tension and perhaps the rear axle was overloaded. Still improper WD was not the root cause failure. Wheel alignment certainly could have contributed but the photo does not show enough of the tread to confirm that. The trailer attitude is also not quite right but again it was not the root cause. Finally it is good that the hitch point is close to the bumper.

[waninae39]

you need to measure the TV and As weigh distribution to ensure the WD and SWAy is setup properly. just looking at it will not help

also, the ball needs to be as close to he rear axis as possible. the further its out , the worse the handling is

get proper 20" tires made for the load and not sports tires, they are too soft and often cant handles the load

IMHO, you should have gone to a reputable dealer and ask them 1st before heading out

[jcl]

Originally Posted by waninae39

get proper 20" tires made for the load and not sports tires, they are too soft and often cant handles the load

In my experience 21” rims do better with 21” tires than 20”.

These are XL rated tires, rated for the load. See the photo.

[Shiny16]

Couldn’t it just be that the rear axle is overloaded? The OP doesn’t even have the correct weight for his trailer as a starting point.

[BayouBiker]

Well, If you do the math, it is very unlikely there was significantly more than the 4,298 lbs that is safe and capable for those tires on the rear axle given the trailer and vehicle unless he had the vehicle loaded with bricks or something.

[Shiny16]

Originally Posted by BayouBiker

Well, If you do the math, it is very unlikely there was significantly more than the 4,298 lbs that is safe and capable for those tires on the rear axle given the trailer and vehicle unless he had the vehicle loaded with bricks or something.

That’s the max weight for the tires yes but doesn’t that assume that everything else is with in limits. If the axle is overloaded could that cause the tires to be riding funky (for lack of a better term) and wear quickly? If the payload is 1279 and you have a family of an unknown number of people driving across the country and you are already basing your numbers on a trailer weight that’s 1000 pounds off wouldn’t it be possible to overload the axle?

[Tomzstream]

Is your vehicle equipped with self leveling? If so, is this photo taken with the engine running and the system active? If it's off, then all bets are off on how your hitch is set up. I can't advise you on how to set it up other than to use the standard method of measuring wheel arches, with the system on. Keep in mind the hitch height will vary as it self levels. Some recommend disabling it (if you can). Personally, I prefer not to mess with the the onboard systems designed by the manufacturer. But I would measure hitch height and level once the vehicle has a chance to adjust and go from there.

[AirstreamCSH]

Originally Posted by Shiny16

You also might want to look up the max trailer weight. The 3500 you list is not GVWR. That’s the empty weight providing it did not have any options or anything added since 2007 when it was built. The GVWR is about 4500. Your off by a 1000 pounds. What’s a “typical “ family trip? How many people are in your family?
The tow capacity for your vehicle sounds fine. Your payload capacity is in question as well as the high performance tires. You might want to head to a cat scale. You might be surprised.

Your question touches the 3rd rail of trailer towing: can I tow this (insert trailer name here) with this (Insert atypical tow vehicle name here). The quoted reply above touches on a point your original post didn’t address but which is all important; namely “what is the tongue rating of your tow vehicle”. Car manufacturers are quick to say how much they can pull but often silent on how much downward pressure you can put on the tongue of the vehicle.

Please post the following and I believe you will have your answer in short order:

1) tongue rating of your Audi hitch taking care to note whether it includes the driver and a full tank of gas or not
2) rear axle rating
3) how many people were in the vehicle on this trip and clarify adult or children
4) a close estimate of the weight of the gear placed in the rear between the axle location and the rear bumper.
5) sidewall rating of your tires for the tire pressure you were using them at.
6) an indication of whether this happened after a long period of 70mph + speeds

As a short answer from personal experience:
1) you have too much weight on the rear of the Audi between your people/cargo load and the trailer tongue weight
2) you can move some weight to the front wheels at the expense of lifting the headlights and blinding oncoming drivers. It’s a balance
3) low profile tires are not what you want for handling loads. Skip the fancy rims and get the smallest reasonable rim available for your vehicle and the tallest sidewall
4) move some weight from the cargo area and place it directly over the axle in the trailer while driving
5) keep speeds below 65mph
6) do the 3 weight test at the CAT scale once you’ve done the above. The result will surprise the heck out of you

[pteck]

Originally Posted by BayouBiker

Well, If you do the math, it is very unlikely there was significantly more than the 4,298 lbs that is safe and capable for those tires on the rear axle given the trailer and vehicle unless he had the vehicle loaded with bricks or something.

To emphasize this, load rating is not great if the assumptions are wrong, particularly tire pressure.

Tires: Lionhart LH-Five 295/35R21XL 107W
Max Load: 2,149

The max load rating is only valid at the max inflation pressure of 49 PSI.

Normal tire pressure is stated in the Audi manual for 35 PSI rear - with a load capacity of ~1856 lbs per tire, or 3,712 lbs rear axle.

It is also stated in the manual for "full load condition" to inflate to 49 PSI, where then your math works out.

This is likely the crux of the OPs issue. If he was even a bit under standard tire pressure, he'd be closer to 3,000lbs tire capacity, and I bet this was his issue. Yet he should also make other changes based on my previous recommendation to increase overall margins.

[kgottleib]

I am finding this post interesting, thanks to everyone for providing expertise.

I have a basecamp 20x on order, current tow vehicle is a jeep grand cherokee limited EcoDeisel model, w Jeep heavy duty tow package that includes an electronic system for sway \ WD. I thought at first I was all set and wouldn't have to consider anything but after reading this post I am now thinking I need to revisit my thoughts on whether I should purchase external sway kit and WD system. Jeep makes great claims about its tow ratings but when you start to dig deeper you see that there is so much more to this than meets the eye. I think I'm going to have to put my own post up to ask for some expertise with my setup before I run into these issues. I am going to have to pick up the Basecamp at a dealership 2 hours from home and I want to make sure that first trip home is a safe one.

I rented an Airstream Gunnar Safari 16 to see how my jeep would perform and it was fine as far as I could tell, didn't sway, super easy to tow, accelerated up hills... but the Basecamp 20x is about 900lbs heavier.

Another concern I have is figuring out the tongue capacity of my jeep, for some reason there is a lot of conflicting info out there and I've seen charts showing tongue capacity for some jeeps at 350Lbs, that's not a lot! My ecodeisel typically isn't inlcuded in many of the publications about jeeps you find on the web, so its a real pain getting answers. I called jeep and opened a ticket w support about it and all they said was your tongue weight is 10 to 15% of the trailer.. WTF is that supposed to mean if you are trying to figure out how much your jeep can accomodate? stating that your tonuge weight should be 10 to 15% doesn't tell you how much your jeep can actually handle.. what your jeep can handle depends on how its built \ equipped, so I'm lost when people provide these vauge answers..