W163. To lower or not to lower.

[Martyn_n]

That's the question really.
We have a w163 ml270 which we predominantly use for towing our caravan. Whilst it tows well enough the remove able tow ball is a little too high resulting in the caravan being completely level when towed; best practice for stability is for the front of the caravan to be slightly lower. For this reason, and fuelled by gin, I have purchased a set of H&r springs. The question is has anyone any experience of doing this from a ride / handling perspective and any strong views about whether I should actually fit this impulse buy?
Ps I know all about the pitfalls of trying to split the existing springs and shocks to recover the top plate for reuse.
Thanks in advance. Martyn.

 

[Jane270ML]

Not had any experience with lowering my ML, or towing, but the link below maybe of some help?


Looking for wheel/tyre size recommendations for my W163 ML - Mercedes-Benz Owners' Forums

 

[Martyn_n]

Not had any experience with lowering my ML, or towing, but the link below maybe of some help?


Looking for wheel/tyre size recommendations for my W163 ML - Mercedes-Benz Owners' Forums

Thanks Jane. It looks like the only advice on that thread was to wind the front up to maximum to give best ground clearance, completely opposite to what I wish to achieve.
My main concern is that the back will get stiffer but even with lowering the front will retain the same compliance. Of course this may kill some understeer off but could also fundamentally upset the balance (Look at me talking about subtleties such as understeer on a vehicle that handles like a narrowboat, get a grip!!!)

 

[Bobby Dazzler]

Our W163 was rock steady when towing so I'm not sure it's strictly necessary, but that doesn't mean you shouldn't do it! We had work done on the suspension on ours and I seem to remember the dealer said the springs and shocks are a single unit, but I've read that they can be separated. I also remember it all being hellishly expensive!

I'll be interested to hear more...

 

[Martyn_n]

Our W163 was rock steady when towing so I'm not sure it's strictly necessary, but that doesn't mean you shouldn't do it! We had work done on the suspension on ours and I seem to remember the dealer said the springs and shocks are a single unit, but I've read that they can be separated. I also remember it all being hellishly expensive!

I'll be interested to hear more...

You are correct, as far as Mercedes are concerned the rear springs / shocks are a single unit. This is why I need to split it even though I intend to replace both I need to reuse the top plate as you can't buy it separately. I agree that it tows very well but any incremental improvement can only make the whole experience less stressful. Think I will give it a go, I can always swap it back, the question is should I do it before our three weeks in France next month!?

 

[merc85]

Why not buy a Drop plate instead of lowering a 4x4

 

[Martyn_n]

Why not buy a Drop plate instead of lowering a 4x4

It's a removeable swan neck towbar so that is not an option without swapping the towbar. I have a completely irrational hatred of visible towbars on a car that isn't towing hence splashing out on the westfalia one. So even though your option is probably more sensible and likely cheaper and easier I won't be taking that route. Thanks for the input though.

 

[Bellow]

My main concern is that the back will get stiffer but even with lowering the front will retain the same compliance. Of course this may kill some understeer off but could also fundamentally upset the balance (Look at me talking about subtleties such as understeer on a vehicle that handles like a narrowboat, get a grip!!!)

Modern practice is to have slighter stiffer rear springs such that the bounce frequency is dissimilar to that at the front frequency to quell pitching. Aftermarket springs will emulate that frequency variation.

 

[Bobby Dazzler]

You are correct, as far as Mercedes are concerned the rear springs / shocks are a single unit. This is why I need to split it even though I intend to replace both I need to reuse the top plate as you can't buy it separately. I agree that it tows very well but any incremental improvement can only make the whole experience less stressful. Think I will give it a go, I can always swap it back, the question is should I do it before our three weeks in France next month!?

Unless you can fit them, test with the caravan in tow, and swap back again if needed) in ample time, then I would be tempted to wait. But I'm sometimes too cautious!

 

[Martyn_n]

I wouldn't call that too cautious, it seems very sensible to me. Amazon assure me the springs will arrive tomorrow so hopefully I can do it over the weekend and next Tuesday I need to take the 'van back to the dealers for a temporary fix (pending a big warranty repair). A 20ish mile round trip on a mix of roads which will tell me if I've done the right thing with plenty of time to revert it back if necessary. I'll feed back with the results.

 

[Abb]

Shame it doesnt have airmatic, because for around £400 you could have fitted a lowering module, which may have solved your problem. Lower it and raise it at the push of a button as required.

 

[Bobby Dazzler]

I wouldn't call that too cautious, it seems very sensible to me. Amazon assure me the springs will arrive tomorrow so hopefully I can do it over the weekend and next Tuesday I need to take the 'van back to the dealers for a temporary fix (pending a big warranty repair). A 20ish mile round trip on a mix of roads which will tell me if I've done the right thing with plenty of time to revert it back if necessary. I'll feed back with the results.

Although taking your caravan in for repairs (and temporary repairs at that) isn't ideal, it should provide a good test. What's wrong with the caravan, nothing too serious I hope?

 

[Martyn_n]

I'm afraid it is quite serious. I was washing it after three consecutive weekends away and found a large split in the horizontal top edge of the rear panel. Ultimately needs a replacement rear panel, just going in next week to have it bonded and taped up to keep the water out. Hopefully not too much water damage has occurred already though I have been assured any that is found will ultimately be sorted.

 

[Bobby Dazzler]

I'm afraid it is quite serious. I was washing it after three consecutive weekends away and found a large split in the horizontal top edge of the rear panel. Ultimately needs a replacement rear panel, just going in next week to have it bonded and taped up to keep the water out. Hopefully not too much water damage has occurred already though I have been assured any that is found will ultimately be sorted.

Sorry to hear that. At least it's being done under warranty. Hopefully it will be done to a high standard.

 

[Martyn_n]

Spent a wasted couple of hours this morning, simply couldn't budge the two bolts holding the lower wishbone in place with the limited access available with the car on axle stands so put everything back together again (Including the three 13mm nuts on top of the struts that are a real pain in the behind to remove). Will give it another go soon, but probably not before our big holiday.
Actually it wasn't a completely wasted morning as I spotted and fixed a split cv joint gaiter, cleaned and lubed the spare wheel carrier and a torsion bar drop link that was past it's best was replaced as well. It never ends does it!!?