Depending on the Airstream's weight and if it's equipped with brakes, you'll need a brake controller. Check with your MB dealer to see if a heavier rear differential fluid such as 75W-140 is recommended.
All German SUVs are excellent towing platforms up to their rated maximum GCW.
I have towed with MB, VW and Porsche SUVs and the suspension, steering and brakes are solid and confidence inspiring.
I tow at max GCW on my current Cayenne with air suspension, using a weight distributing hitch and Tekonsha Prodigy P3 wired electric brake controller.
The combination is solid as a rock and comfortable to drive, when driven as it should be. Heavy towing requires driving skill.
W465 G550 tow rating is 7000 lbs, a 16’ Bambi is 3500 lbs. The G will handle this with ease.
Do not change any fluid specs, eg transmission oe axles. The standard fluids are capable of the vehicle performance specifications.
W465 and current 9Y0 Cayenne have similar wheelbases. The Cayenne is a great tow platform and I believe the G should be as well. GLE has a few inches more WB which would be a noticeable improvement at highway speeds.
Not with a G550 but with a GLS550. You 100% want a brake controller, we are in FLAT FLAT Florida and it still makes a rather large difference. In the Georga and NC hills even more so.
Assuming your tanks are empty (but for propane) you really cant tell it is there just going down the highway with the CC on. I was told to even keep our fresh water tank empty to tow - it only makes sense. We never not ever use the bathroom for anything more than #1 from the young ones...so, have no experiance with full fresh/black/grey water tanks.
Wow! A wealth of information. Thank you all for the great comments! Will send pics when I get it all wired up...
Two questions:
1. Is a wireless brake controller a bad idea?
2. Any recommendations on weight distributing hitches? I was told some vehicles are not compatible with this style of hitch.
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