I was playing around building a GLS on MBUSA site and noticed that it gets a class IV hitch. I then went back and looked and the GLE gets a class III. I couldn’t not remember the difference (class III vs IV) very well so I started comparing the difference between a class III and class IV. 90% of the articles I read say a class III hitch only tows up to 6000lbs and then a few and said that it can tow up to 10,000lbs if a weight distribution hitch is installed. If the GLE is rated at 7700 lbs, is this class III hitch sufficient to tow up to 7700 without a WD?
(I understand that you should only be towing 80% of what the vehicle is rated at too, but normally manufacturers don’t supply lower tow hitches than the vehicle is rated at)
Just curious why one gets a class III and the other a class IV when there isn’t much difference between a GLS and GLE towing capacities.

 

@BACnMercedes What prompts the question? Tow rating by the manufacturer and hitch drawbar size (2” for example) are what matters. What towing needs do you have that the hitch class affects, and that isn’t addressed by knowing the vehicle’s rated towing capacity and the drawbar size?

 

Like I said in the original post, just curious as to why one says class III and the other IV when the tow ratings are not that much different.
After reading more today, these industry ratings really are all over the place anyway and the GLS and GLE appear to be identical. So why waste the money/overhead and supply a class IV over a class III.
I knew I remember reading about this somewhere else and I went back and found this.
https://mbworld.org/forums/gls-class...tow-specs.html

 

That difference is in the GVW ratings and vehicles load capacities on the door stickers. I have a GLE and do tow allot but have a proper tow vehicle. Personally knowing the load capacity of my GLE it would never be really safe on the road with anything more than a small single axle lawn mower “trailer” of about 3,500 GVW
Robert

 

My understanding for class rating for hitches is that those number are the minimum capacity that specific hitch must met in order to classify as that rating. So in order for a hitch to be rated at class III, they must be able to handle 6000 lbs, and for class IV, 12000 lbs. It doesn't mean that is the maximum capacity for the hitch. So a class III hitch can in theory handle 6000 lbs up to 11999 lbs (as long as that specific hitch and vehicle is rated for that).

 

I have never heard that theory but it makes sense. Txs.

 

https://www.drawtite-hitches.com/lea...towing-classes

Classes 1 and 2 receivers are weight carrying only, and are non-weight distributing, use a smaller size square drawbar and are distinguished by different weight ratings.

Classes 3 and 4 receivers can be both weight carrying and weight distributing, use a larger 2" size square drawbar and are distinguished by different weight ratings.

Both GLE and GLS have a 7,700lb trailer rating. To achieve this with a non-weight distributing configuration requires a Class 4 receiver. This is the more conservative approach by M-B, rather than to require customers use a weight distributing system to achieve the vehicle's trailer rating of 7.700 lbs. The photo on the M-B site for the GLS shows a trailer with a non-weight distributing hitch. No way of knowing the weight of that particular trailer, whether or not it weighed 7,700 lbs, or less.

Does M-B have documentation on their website or owner's manuals addressing hitch class?

 

From the Drawtite-Hitches site, in addition to the above, and at least as important is:

• Class III hitches used as weight carrying are rated up to 6000 lbs. gross trailer weight (GTW) with a maximum trailer tongue weight (TW) of 600 lbs.
• Class III hitches used for weight distributing are rated up to 10,000 lbs. gross trailer weight (GTW) with a maximum trailer tongue weight (TW) of 1000 lbs.

• Class IV hitches used as weight carrying are rated up to 10,000 lbs. gross trailer weight (GTW) with a maximum trailer tongue weight (TW) of 1000 lbs.
• Class IV hitches used for weight distributing are rated up to 14,000 lbs. gross trailer weight (GTW) with a maximum trailer tongue weight (TW) of 1400 lbs.

This would say the rating is the MAX WEIGHT for the hitch. It also means that for the GLE, you could tow only 6000lb with a weight carry hitch (due to hitch limit) and up to 7700lb with a weight distribution hitch (due to GLE limit).
The Reese-Hitches site has almost identical wording.

 

I'd have to say that there are plenty of inconsistencies in M-B's information. The Build your Car site, as mentioned above, talks about Class III and Class IV hitches, but I don't think the actual hitches are different.
The Owner's Manual for our GLE450 says the towing capacity is 3500kg (7716#) but the tongue weight max is 140kg (308#) which is dangerously low, almost guarantying sway. Obviously that's a misprint, probably meaning that the tongue weight max is 308kg (679#), which kind of fits the old Euro equation of 8% of max rated tow capacity (7700# X 8%=616#). More recently, the M-B hitches were rated at 10% of max tow capacity (7200# X 10%=720#). There is a lot of discussion about this on the Airstream Forum, and CanAm RV Centre's website https://www.canamrv.ca/towing-expertise/

My point is that M-B's trailering specs are all over the board and shouldn't be relied upon.
Throw in an aftermarket accessory maker's data (in this case Draw-Tite), which is NOT talking about the M-B hitch and repeatedly cautions to "read the label" on the actual hitch, and the (vehicle) manufacturer's info.

Addressing the OP @BACnMercedes thoughts about only towing at 80% of a Tow Vehicle's rating - that's a good rule of thumb for trucks made before the SAE J2807 towing standard (2010) which was finally adopted by all truck manufacturers in 2016. Prior to that, tow capacities were driven by the Ad departments, not engineering. Now the 80% rule is obsolete, too.

What does all this mean? It means that the only reliable way to determine a safe towing capacity is by reading the Driver's Door Pillar sticker showing payload (it varies depending on optional equipment - a Pano roof will decrease payload by several hundred pounds). The payload is also the limiting factor in pickups - many half tons have payloads less than a GLE. In all cases, our GLE/S are already equipped with the bigger alternator and cooling packages that are part of pickup's optional towing packages, and our brakes exceed the size and stopping power of 3/4T pickups, and probably 1 Ton, too.

Since I push the payload limits with tongue weight, by carrying quite a bit of stuff in the cargo area of our ML (haven't towed or hooked up the 450 yet), I go to the scales when loaded for a trip to weigh each axle and make sure I am not overloading the front or rear axle. I have quite a bit of leeway on axle weights, even though I am over on the payload.

I also carry a Sherline tongue weight scale that I use from time to time if I change my trailer loading habits. https://www.sherline.com/product/she...-weight-scale/
As an aside, I think Sherline's Trailer Loading and Towing Guide is the best all-around towing guide. https://sherline.com/wp-content/uplo...ooklet_web.pdf It's unbiased, not selling a hitch, WDH, or any other product other than a scale.

Reading the label on the hitch on the GLE350 4Matic service loaner in the garage, the weight ratings are: with WDH - 7500#/600#, and with only weight carrying - 7715#/600#. Seems odd, so I go back to axle ratings (GAWR front and rear).

No matter what, I prefer the towing capabilities of our M-B's over any pickup I've towed with. Modern suspension and brakes, combined with the stiffness of our uni-body construction and short rear overhang, are superior. But in any case, setup and loading are more important than any rating.

 

Great information @mikapen but I do disagree on the GLE being better than most trucks. I’ve towed my current boat with a Tahoe, 3 Tundras, and my current GLE 400. The Tahoe had no problem pulling it but the boat squatted the rear terrible bad. I then moved through the tundras and you could barely tell the boat was back there. As for the GLE , it pulls the boat unbelievably well. Stopping takes a little more and the unibody sounds like a tin can getting twisted apart. Yes I’m comparing the V166 and not the V167 which may be different.

 

There are a couple of ways to get rid of most of that noise. One is a Hitch Clamp that takes the slop out of the receiver. There are a lot of different ones but hers an example.
https://www.walmart.com/ip/OxGord-Hi...AaAnc-EALw_wcB
The clamp is a little bit of a pain because it adds another step to tighten it down.

The second method is more involved but better long run. The rattle comes from the clearance between the receiver parts and the short piece that lets things slop starting or stopping. The ball mount rocks up and down making a lot of noise as you brake or accelerate. The nature of an SUV vs a truck let’s all the noise into the cabin. I took an extended length Ball Mount and placed it to the back of the receiver and marked the location to drill a new hole. The longer portion in the receiver still moves up and down a little but noise in the car is almost gone.i would post a picture but the Ball Mount is at another location. I had good success with the GLE but our Audi has a short receiver so I use a clamp on it.

 

I have to admit that I haven't towed with a pickup since a 2005 Ford 3/4T, which was before the SAE J2807 specs. We changed to an E250 van for the race car because the F250 pickup had just too much frame flex for the abuse we gave it. My M-B comparison was with a W164 Bluetec, which was better than the truck in every way I can quantify.
"...barely tell the boat was there" describes our experience, but is an understatement for our W164, especially in horrible situations, including braking/avoiding an errant bounder on downhill Wolf Creek Pass. Or the fridge that fell off a truck in Chicago rush hour. Never could have done those maneuvers in a pickup and trailer. Again, loading and setup is important as we approach the tow capacity limits.
I think our W166 (also Bluetec) was a step down from the W164, in suspension and, as you say, the twisted tin can effect (great analogy!). In between we had a Diesel Cayenne.
The V167 gives a much more stable platform, doesn't creak and groan, and handles with the base steel-suspended Cayenne's and air Audi SQ7 - or maybe even better.
Hoping for a good experience towing with the new 450.

 

I agree about noise into the cabin, but you reduce your load limits and decrease your tow vehicle's control of the trailer, by extending the distance from the ball to the rear axle. It can be a significant reduction, and can invite sway by giving the trailer mass more leverage over the SUV. (Short ball-to-axle ratio is one of the advantages our SUV's have over pickup trucks.)
I was tired of all that racket back there when pulling our utility trailer, then I found that there seems to be a big variable in "2 inches," as in the actual measurement of the stinger. I borrowed a stinger with a smaller ball, to tow another utility trailer from a friend and - it was silent. The difference - 1/64" or less of cross-section. My WDH doesn't have that fit/noise problem, but I found a stinger with the proper measurements for towing without WDH and the noise is gone. Stinger made in Germany, not China.

 

My modified stinger doesn’t stick out very far...about 3” more-felt stock one was too close to the bumper. I liked that length better than the stock one or would have cut some off. Where did you find a German made product? I spent a fair amount of time looking and while the clearances weren’t bad, the length behind the bolt was always very short so fulcrum point was not good. The extended stingers might be German...didn’t see a point of origin but didn’t look. The fit was so tight I had to grind the interior around the holes of the receiver where the press for the holes had distorted the inside clearance.
I only tow about 3,000lbs...

 

I am not sure if there is a standard of the class rating for hitch, as it seems like different place provide different figure.
In https://www.curtmfg.com/types-traile...s#HitchClasses and https://www.etrailer.com/faq-hitchclasses.aspx, it seem like the number is different than what you listed.
Class III (CURT website): GTW up to 8000 lbs, with WD up to 12000 lbs
Class III (etrailer website): GTW 3500 - 8000 lbs
Class IV (CURT website): GTW up to 10000 lbs, with WD up to 12000 lbs
Class IV (etrailer website): GTW 5000 - 12000 lbs
The e trailer website has a range, vs curt has a max rating.

I think it might be best to follow that the car manufacturers (in this case, mercedes) recommended. Since they built the car, their number should be the most accurate for our car.

 

Does anyone have any experience or opinion on this solution to hitch rattle?

https://www.rattlefreehitch.com/

Thanks

 

just noticed that "you must have a ball hitch with a hollow channel"

 

Drawbar (“stinger” is erroneous) to receiver rattle is common in German vehicles. The tolerance is not well understood and the inch-based dimensions add to the problem. An inch-based measurement with improper manufacturing tolerance means excessive clearance between drawbar and receiver, resulting in rattle. I am referring to receiver design, because this is what MB, VW and others are responsible for. The drawbar is purchased by the vehicle driver at a retail establishment.

My previous Touareg had terrible receiver rattle. Wife’s 4Runner had a small amount, almost none. My W166 has none, or very little. All three vehicles I refer to have used the very same drawbar over the years.

Suggestions to reduce rattle are to use a solid (not tubular) drawbar for the heavier mass, and the longest insertion depth drawbar you can find, with the shortest extension length you can find.

 

Most rattle in my experience is from the ball mount piece moving up and down in the receiver. My pins and locks don’t have the slop depicted in the advertisement.
The new Gen GLE has a decent length receiver with the hole close to centered. Too many ball mounts are either a little smaller diameter or more often too short behind the hole exacerbating the up and down motion.

 

Zengshengliu, maybe I did not make my point clear. I was trying to show that it may be necessary to use a weight distribution configuration to safely tow 7700lbs with the GLE.

For those not similar with weight carry and weight distribution configurations, these are two ways to set up your rear receiver trailer hitch. The weight carry setup is the simple “put the trailer coupler on the hitch ball” and go. A weight distribution configuration effectively adds bars/springs between the hitch (tow vehicle) and the trailer to help level the tow vehicle (the GLE in this case) and spreading the trailer tongue weight between the hitch (tow vehicle) and the trailer axle(s). An internet search will show examples of both configurations.

The “class” of the hitch (I, II, III, IV, V) is not the important number, the important hitch number(s) are the weight carry and weight distribution limits (along with tongue weight of course). These numbers show the hitch’s maximum weight limits for the specified hitch configuration (weight carry or weight distribution). If the weight carry limit for the GLE’s hitch is less than 7700lb, say 6000lb in the case of the Drawtite-Hitches hitch, it would not be safe to tow 7700lb. The weight distribution configuration (10,000lb limit for this example) may be required to tow the 7700lb with the GLE. I have not looked at the GLE’s hitch, these are just examples.

The 7700 lb towing capacity is simply one element in determining what can be towed safely. There are other component limits to consider. For example, Mikapen brought up the limits on single axle weights which could limit the max towing to below the 7700lb via the tongue weight. If you put a lot of “stuff” in the back of the GLE, that “stuff” and the tongue weight may exceed the rear axle limit of the GLE. Again, this could make towing 7700lb unsafe. You also have the GCWR, or gross combined weight rating. This includes the weight of the loaded vehicle and the loaded trailer. It is also required that the ball on the hitch be rated high enough to handle the trailer. Other considerations are mentioned in the manual.

To be honest, when I started towing my 5k pound travel trailer with my dually diesel and class V hitch, I did not do a total look at the configuration. However, when I started towing my 7+ ton 5th wheel, I looked at it all. The 5th wheel hitch, the rear axle limit and on and on.

In determining the tow capacity number of vehicles (7700lb for the GLE), I have found no reference to the hitch configuration, but simply a weight assumption for the hitch itself (how much the hitch weights).

Again, we do not have our GLE yet, so I do not know what the hitch is rated but simply looking at the number on the door, especially when you are approaching that limit is not sufficient to ensure you are towing safely.

 

Very good points. Like Beer Rabbit I do currently tow with a one ton diesel and have been towing "stuff" for many years with various vehicles. Sometimes I feel like a hotshot OTR driver towing to show events.

The hitch noises are usually caused by improper too low tongue weight causing a bit of rising and falling as road dips are encountered while towing. Currently My one ton truck car trailer hitch noises usually are when nothing is in the trailer (rare).

I thought an earlier comment about the superiority of our GLE's interesting. Agreed the new generation of half ton pickups are not really designed for towing as well, as most of the 3/4 ton trucks, but those are full frame vehicles. That is why I made the comment in an earlier post that I wouldn't tow anything over a 3,500 GVW single axle landscaping trailer with my GLE. Has anyone besides me looked at the payload capacities of their GLE. It is in line with most similiar sized SUV's(low) plus the dreaded turbo lag in the GLE's doesn't help matters.
Robert

 

I don’t think the noise I’m hearing has much to do with the receiver and hitch part. It actually sounds like someone is twisting a huge tin can sometimes during acceleration and braking. I did remember their being a lot of play and hitch noise on my tundras from the receiver bouncing around but this sounds different and I’m using the same receiver I had then.

 

hmm that sound is familiar with my car hauler bumper tow rig. Due to internet speeds and weight I use an Equalizer Brand 4 way bar equalizer and sway system. I hear something similar at times mostly on slow speed turns though. The noise the hitch assembly makes if not enough tongue weight is more heavier metallic.clunk.
Robert

 

Beer Rabbit, I think I like that better.

 

That doesn’t sound like anything I ever experienced with my GLE450 or any other vehicle. I have towed different things for 40+ years with trucks and SUV’s. My Boat & one Travel Trailer were over 10,000 lbs towed on the Alcan Highway to Alaska and numerous 2-4 thousand mile trips. While I normally only towed around 3000 lbs with my GLE, on one occasion I towed close to twice that about 90 miles on a lot of curves and some rough road. Not a peep. Trucks have an isolated cab from the bed so any hitch noise is more subdued. Equalizer hitches make some creaking noises at times.