X5 impressions vs ML - Benzworld.org

roadsession · 07-15-2005, 10:08 PM

So as some of you may know our 2nd car is a bmw 530i

Recently took it in for service and had an interesting experience with the X5 loaner car.

It was a 2005 X5 3.0i with 2,200miles on the odometer.
I drove it for 2 days covering about 200 miles.

I was totally shocked by what i thought would be a more quieter rattle/groan free unibody suv. The thing squeaked and groaned more loudly than my 6 year old ML with 80K miles on the odometer.

Oh well, there goes my theory that the unibody would somehow magically make things quieter

2bmj · 07-16-2005, 02:34 PM

My other unibody vehicles all had body misalignment problems and I was not very hard on them. I hope the new w164 holds up. I really like the fact that my w163 is built on a real chassis. I havenâ€™t seen any sign of misalignment on my ml. My opinion is that the unibody designs just don't have the inherent rigidity of the frame designs.
Joe

Noodles · 07-16-2005, 02:57 PM

I was let down when I found out that the W164s were uni-body. The body on frame design of the W163s is much tougher. Also more expensive to manufacture so it is apparent as to why MB went to a unitized design. 90%+ of the MLs never see dirt or off road so MB is basically building to market and not towards durability.

As far as the X5 goes, I have driven several and was not very impressed. I did not like the steering or the all wheel drive system. The thing felt like it was clumsy.

Drew · 07-16-2005, 03:15 PM

Quote:

Noodles - 7/16/2005 1:57 PM

I was let down when I found out that the W164s were uni-body. The body on frame design of the W163s is much tougher.

This is not necessarily true. The W164 has a much more rigid bodyshell than the W163. The new ML has an unprecedented 64% composition of HSLA (High Strength Low Alloy) Steel which is 300% stronger than regular steel. The W163 has just over 1/3 of this amount of HSLA steel, namely the entire frame of the W163 is HSLA steel. Simply amazing because HSLA steel is very expensive; this partly accounts for the price increase over the W163.

This is an enormous amount of HSLA steel as the W211 E-Class had something like 48%, which is already more than even the W220 S-Class!

Noodles · 07-16-2005, 03:46 PM

Wow that is impressive about the HSLA makeup of the vehicles. I can see why the 164 is more rigid, but will the frame of the 164 handle the abuse as well a 163? Rigidity does not always translate to durability for certain components.

Thanks for the knowledge.

Drew · 07-16-2005, 07:47 PM

Quote:

Noodles - 7/16/2005 2:46 PM

Wow that is impressive about the HSLA makeup of the vehicles. I can see why the 164 is more rigid, but will the frame of the 164 handle the abuse as well a 163? Rigidity does not always translate to durability for certain components.

Thanks for the knowledge.

You're most welcome. I can totally understand where you're coming from. [:)]

We were told in training that the dramatic increase in HSLA steel content was partly made so as to improve the W164's off-roading and towing performance, despite the shift to a body-on-frame design. Traditionally, body-on-frame vehicles have been more suitable for towing over long durations, and arguably this may still be the case as the frame takes the stress rather than the monocoque. However with such a rigid body monocoque shell, there are no durability issues predicted.

Also, Range Rovers are now unibody designs, and no one questions their off-roadability. Even the Touareg and Cayenne are unibody designs and they too are good off-road, from what I've read. What's interesting though, is that Audi's new Q7 SUV, based on the same platform as the latter two, is much lighter since it does not have the same structural fortification as it is not designed for more than light off-roading.

Noodles · 07-17-2005, 12:26 AM

Ahhh, that makes sense. The other unitized vehicles you mentioned do have a solid record so far, but our Audi All Road was so tempermental that in less than 15k miles I dumped it.

What disturbs me about the Benz's over the last several years is a comparison to a Ford product I have owned since 96. A SVT Cobra coupe. I had Dario the owner of Steeda go to town on the brakes and suspension. No engine mods at all due to the warranty. Well that vehicle only has 47k on the odo, but over 20k of those miles was under full race condtions. Brake temps of 6-700f, engine speeds of 6-7k RPMs. No failures to this point.
The race wear and tear should equate to over 200k in real world driving and this Cobra is still tight.
We welded in sub frame connecters. Then the 8
point cage. Obviously making the car very stiff compared to a stock Cobra. It has won many trophies on the track and a a couple of show trophies. So what baffles me is how can a product from Ford be so much tougher than a Benz?
I have a 190 2.3 16v. It is pristine and seems to be as tough as the Cobra. My 1990 300e has 224k on the odo and seems to be more than willing to outlast my 99 ML430.
Part of my spin on this is that the ML puked up a tranny that so far is not resolved and I am trying to get the dealer and MB to give me some assistance. It is not the money, but the principle.
Just 3 months ago I called the service manager at the dealer we bought two MLs from with my concerns about the tranny and changing the "lifetime" fluid. He told me not to worry and now I am looking at at least 5-7k to fix the damn thing. I love the driving dynamics of the MLs but am quickly losing patience with MBs cavalier attitude about denial of any problems that were their engineering flaws.
At the same time they are trying to swoon me into a SLR McLaren for a track toy and they are being less than helpful in helping with what is a known flaw in the 722.6 trans. What to do? My wife wants to keep the truck and fix it. I want to set it on fire. Hopefully the MB powers that be will at least offer some help. I am not asking for a free repair, only some assistance to make it a fair deal. I will keep you guys here posted on the ML tranny issue.

Thanks again,
Noodles

marcelc · 07-17-2005, 07:10 AM

Quote:

Noodles - 7/17/2005 10:46 PM

Wow that is impressive about the HSLA makeup of the vehicles. I can see why the 164 is more rigid, but will the frame of the 164 handle the abuse as well a 163? Rigidity does not always translate to durability for certain components.

Thanks for the knowledge.

Whenever I asked a dealer about chassis strength they respond with information on chassis rigidity; I think the two are separate quantities.

Extra rigidity will make the vehicle handle better, especially at speed, but if it is not strong enough for a particular situation it will mean the vehicle twists and becomes scrap. I have heard of this happening to an X5 in an extreme off-road situation.

Whilst I am not claiming the W164 is not strong enough (I don't know), I won't accept information on rigidity in place of information on strength.

DelJ · 07-17-2005, 09:08 AM

You are correct: strength and stiffness are two separate characteristics. A potato chip is stiff but not strong, while a rubber band is strong but not stiff. Stiffness is the ability to resist elastic deformation while under load, strength is the ability to resist permanent deformation (damage) after the load is removed. It is quite possible to have a stiff frame that is not very strong, or any other combination.

One should also note that high-strength alloys do not increase stiffness. Stiffness for a given weight is optimized by geometry.

DelJ

Quote:

marcelc - 7/17/2005 6:10 AM

Whenever I asked a dealer about chassis strength they respond with information on chassis rigidity; I think the two are separate quantities.

Whilst I am not claiming the W164 is not strong enough (I don't know), I won't accept information on rigidity in place of information on strength.

marcelc · 07-17-2005, 09:41 AM

Thanks DelJ - perfectly put!