Recommended trailer hitch ball setups



https://mbworld.org/forums/gle-class...on-my2024.html mentions
The 2" seems to correlate with the 2-inch ball rise mentioned above.
The 7.5" seems to be the distance from the center of the pin to the center of the ball. Is there a name for this? Is this the ball mount length?
What is the 2.75"?
What hitch ball setup do you use? Do you recommend it?
Last edited by Splaktar; Jan 27, 2024 at 02:10 AM.




The diagram is likely laying out the recommended limits for the ball position. Center of the ball no more than 7.5" from the back of the hitch pin. 2" raise or 2.75" drop from the top of the hitch receiver. As noted using the 4" raise with our W164 was significantly better than the lower ball position with our trailer. Yours might be different. The height of the ball will also have some impact on the tongue weight. Higher = less and lower = more. Try one and see how everything feels stability wise and then adjust if you think it needs it.
Last edited by jkaetz; Jan 27, 2024 at 09:02 AM.



They also offer a 7-pin to 4-pin converter to work with their trailers that have surge brakes and don't need a brake controller. It's $15.




They're likely selling the common 2" drop or 3/4" rise hitch. This will likely also be too low for the GLS receiver.
You'll likely want a 2" - 4" rise. These will be sold as 4" or 6" drop hitches. You'll just want to flip it over.
Don't know how heavy you're planning to load it but I estimate our boat, trailer (surge brakes), and boat cargo to be around 5500 when fully loaded. Even with cargo and people in the ML we never had any issues. I did raise the rear tires to the recommended max load PSI vs the normal PSI. We even had an instance where the trailer brakes were failing but the ML's brakes never complained. Given the GLS and 167 platform should have improved over our 164 ML I can't imagine you'll have any trouble.
We also use a locking hitch pin, but don't leave it in when you're not using it or it'll likely never come unlocked again. Granted I think most of them will break with a good whack from a motivated thief so as with most things they keep honest people honest.
Last edited by jkaetz; Jan 27, 2024 at 05:59 PM.



Is that a minimum or maximum length?




For best stability, it's best to stay under the 7.5", and the car's ability to control the trailer increases even more with a shorter ball mount.
In short, Shorter is Better. Is there a reason you want a longer ball mount?




https://www.amazon.com/s?k=7+to+4+tr...s_ts-doa-p_1_6
They're likely selling the common 2" drop or 3/4" raise hitch. This will likely also be too low for the GLS receiver.
https://www.amazon.com/CURT-45134-Fu...t+hitch&sr=8-8
You'll likely want a 2" - 4" raise. These will be sold as 4" or 6" drop hitches. You'll just want to flip it over.
https://www.amazon.com/CURT-45056-Lo...+hitch&sr=8-16
https://www.amazon.com/CURT-45064-Li...p+hitch&sr=8-2
Don't know how heavy you're planning to load it but I estimate our boat, trailer (surge brakes), and boat cargo to be around 5500 when fully loaded. Even with cargo and people in the ML we never had any issues. I did raise the rear tires to the recommended max load PSI vs the normal PSI. We even had an instance where the trailer brakes were failing but the ML's brakes never complained. Given the GLS and 167 platform should have improved over our 164 ML I can't imagine you'll have any trouble.
We also use a locking hitch pin, but don't leave it in when you're not using it or it'll likely never come unlocked again. Granted I think most of them will break with a good whack from a motivated thief so as with most things they keep honest people honest.
Here's one that fits the hitch specification label:
https://www.etrailer.com/Trailer-Hit...RT/C45036.html
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For best stability, it's best to stay under the 7.5", and the car's ability to control the trailer increases even more with a shorter ball mount.
In short, Shorter is Better. Is there a reason you want a longer ball mount?
Some more numbers, U-haul recommends an 18" trailer height for their trailers. The top of the ML hitch is 14" and I suspect this is the same for the GLS (ours isn't home for me to measure at the moment). This would mean you still need a 4" rise to get to the recommended 18".
https://www.uhaul.com/Tips/Trailer-H...ur-Hitch-5227/
Last edited by jkaetz; Jan 27, 2024 at 06:02 PM.
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Some more numbers, U-haul recommends an 18" trailer height for their trailers. The top of the ML hitch is 14" and I suspect this is the same for the GLS (ours isn't home for me to measure at the moment). This would mean you still need a 4" rise to get to the recommended 18".
https://www.uhaul.com/Tips/Trailer-H...ur-Hitch-5227/
It's important that any trailer be level or it will tend to submarine if low, or rise up if higher than the ball, and generally provide less control over the trailer. As you found out.
I'll bet you can find the correct rise without going longer.
I'll go measure my hitch and see if e-Trailer lists a suitable one. After the playoffs....
Last edited by mikapen; Jan 28, 2024 at 02:21 PM.



It's unfortunate that all of the ball mounts I find are designed to lower first, then the flipped-over rise is some variable fraction of the lowering distance.
Does anyone recommend the more expensive ball mounts that have adjustable ball height (and even two ball sizes)?




You said that U-Haul recommends an 18-in tongue height, but everything I see with a 4-in rise is either really long or another compromise.
If you/they would accept 1 in lower, here's a hitch from e-trailer that should work for you:
https://www.etrailer.com/Trailer-Hit...er/989892.html
Generally speaking, tongue down is better than tongue up if you have to make a choice.
Regarding my comment about having to de-rate the hitch if it's longer than the 7 1/2 in (which the above hitch is not), it's an incremental thing. Like adjusting your tire pressures to the correct inflation for towing.
Every little bit helps.
I'm facing the same thing, getting ready to rent an enclosed trailer.
Those adjustable ball mounts are awkward and clunky, with another high torque set of bolts that I'd try to avoid.
I'm not fully decided, but I think I'm going to settle on one I linked above.
(I have a half a dozen ball mounts, for two different cars and three trailers, ball sizes 1 7/8 to 2 5/16. I don't want to be loosening and reapplying 250 ft lb of torque and a new spring washer every time I change trailers.)
Last edited by mikapen; Jan 29, 2024 at 01:34 PM.




You said that U-Haul recommends an 18-in tongue height, but everything I see with a 4-in rise is either really long or another compromise.
If you/they would accept 1 in lower, here's a hitch from e-trailer that should work for you:
https://www.etrailer.com/Trailer-Hit...er/989892.html
Generally speaking, tongue down is better than tongue up if you have to make a choice.
Regarding my comment about having to de-rate the hitch if it's longer than the 7 1/2 in (which the above hitch is not), it's an incremental thing. Like adjusting your tire pressures to the correct inflation for towing.
Every little bit helps.
I'm facing the same thing, getting ready to rent an enclosed trailer.
Those adjustable ball mounts are awkward and clunky, with another high torque set of bolts that I'd try to avoid.
I'm not fully decided, but I think I'm going to settle on one I linked above.
(I have a half a dozen ball mounts, for two different cars and three trailers, ball sizes 1 7/8 to 2 5/16. I don't want to be loosening and reapplying 250 ft lb of torque and a new spring washer every time I change trailers.)
That said the ML does not have airmatic, the 2.75" rise might be enough combined with airmatic's load leveling. It's probably going to be a case where you'll have to try both and see which one works better for you. It'll likely be this summer before I can put the boat behind our GLS and see how it behaves.







I am not sure why your new thread is in the GLE forum though 😇








Picked up my 6x12 U-Haul today. Here are my measurements and thoughts (167 GLE but should be the same as a GLS).
I flipped a Reese hitch, so rise is now 3.5". Pin to ball center 10.5". Ball height 17.5" in Comfort setting. I believe cars maintain the Comfort height at all speeds when your 7-pin is connected.
It's a little out of spec, but well within capacity with the minor de-ratings necessary by the out-of-spec measurements.
The trailer is 4,000 lb gvw with 400 lb tongue weight.
I intend to put more tongue weight than the minimum - I'll aim for 600 lb.
As an aside, I was VERY pleased to see the tires are Carlisle Radial Trail HD, which has an 82 mph speed rating and plenty of capacity. The other acceptable trailer tire to me is a Goodyear Endurance load range D.
Most trailer tires are rated at 55 mph top speed, based on their inability to shed heat at speed. Carlisle and Goodyear (in that order) developed compounds and constructions that allow better heat dissipation and therefore the higher speed rating.
We're in record heat, and I'd stick to the 55 mph rating if that's all the tires gave me. But with the Carlisle's, I can Cruise at a reasonable speed. Yay.
Last edited by mikapen; Jun 25, 2024 at 06:21 PM.


