KDW2 = Horrible in Rain

[Rider90]

Yeah I didn't want to admit it the last time I lost it with these tires, but I'll admit it now. I took a 90* turn at about 10 MPH and the back end wanted to get ahead of the front end. If it wasn't for T/C I would have had an accident tonight in the rain. Obviously I used caution in the wet weather, and I slowed through the turn, and all of a sudden I had thought I hit an ice patch.

I didn't want to leave this to your imagination since I could bring it up on the map, so here is the turn: (Circled)
http://midwestpanthers.net/topmap.jpg
as you can see, it is pretty sharp. Just before an on-ramp to the freeway.

I've taken this turn many times with the stock KDW tires and have not had a problem. They followed through just like they should have where as these KDW2s lost it. Tires are @ 40 psi with a max of 50 on the sidewall. Say what you want about my driving but I thought you guys pondering these tires should know that even though they provide exceptional traction during the dry weather, the wet weather leaves a little more to be desired, at least in the mind that this tire should out perform the stock KDW. Maybe I'm all wrong for thinking that, but the KDW stands for "Key" feature "Dry" and "Wet" traction (Ref: Tire Rack (http://www.tirerack.com/tires/tires.jsp?tireMake=BFGoodrich&tireModel=g-Force+T%2FA+KDW+2&vehicleSearch=false&partnum=555VR8GFTAKDW2RF&fromCompare1=yes)) also having a 9.4 dry rating and an 8.8 wet rating.

:alone:

[Donny Carlson]

BF Goodrich rates both the KDWS and the KDW2 as "10" for rain. It rates the KDW2 higher (better) for road noise and handling.

It is possible you hit a patch of oil or other lubricant?

[Rider90]

Donny,
That crossed my mind too. But this exact thing has happened twice now, and I suppose it could happen both times where I hit some oil on the road, but it has the same behavior in a straight line. I thought this tire would atleast out perform the stock KDW in a straight line when it is wet and it doesn't.

By saying what I did above I wanted to give the future buyer the "scoop" on the tire before he makes a purchase because it is something I would appreciate if I were in his shoes. I'm not saying this to bash the tire, because hey, I spent money on it and it would only make me happy to say it performs great, but it lacks in one area.

[Bluerauder]

It is possible you hit a patch of oil or other lubricant?
My thoughts as well .........

[BruteForce]

Not my experience at all... though I am running lower pressure (36 IIRC) in the rear than you. Do you have any other suspension mods?

I can certainly spin them through a wet corner, but the tail end tracks correctly. I've also got the Naake shocks, aftermarket control arms & sway bars (front & rear). My front end is actually raised slightly from stock (like 0.34").

[Dark_Knight7096]

Yea that is strange because I do not experience any problems with them in the rain unless i'm driving like i do when it's dry, lol. Then again you never know maybe conditions were just right a few times maybe you got a cruddy set of tires, who knows, a lot of X factors.

[Rider90]

Maybe it could be the psi difference? 4 lbs. No suspension mods (not enough $$$) :) Glad to hear you guys are having good experiences with yours, maybe someone peed on mine during the creation process and it messed something up..

OK which one of you wants to trade?? :D

[Gunslinger]

Maybe it could be the psi difference? 4 lbs. No suspension mods (not enough $$$) :) Glad to hear you guys are having good experiences with yours, maybe someone peed on mine during the creation process and it messed something up..


I've heard of this happening before. Factory workers mixing their own urine into the tire creation process... It is a sad day when you can't but a set of tires without some union pee mixed in to ruin your traction. I'd head straight to the production floor myself! Good luck with your urine slicks

[BillyGman]

I haven't tried those tires yet, but why do youssure so high in them? 40 PSI is a lot. I would think that 32 PSI would be a whole lot better.

[SergntMac]

Rider, I'm glad you and your MM are okay. The KDW2 is probably the best all around road tire available today, I love the tread design. However, no tire is ideal for all road and driving conditions, and your experience serves to remind us that the relationship between the rubber and the road is affected by many external conditions. My Pirellis are highly rated too, and it's still rather easy to throw my MM into a spin. All it takes is power and weight, and the Marauder has a healthy share of both on tap.

In any car, control depends on four contact patches with the pavement and in hard turns, this relationship is easily disturbed. The inside of the turn radius is the "lift" side, and the outside is the "grip" side. Even on perfectly prepared dry surfaces, such as skid pads, when the lift exceeds grip, control diminishes in an ever increasing scale. The "looser" your suspension, the sooner weight transfer and inertia steal your control.

On a hard left turn, the left rear tire is the first to lose traction, and the right front tire is the first to be overpowered by this weight transfer. As the turn continues, weight transfer creates even more lift and compression, and once you add our natural tendency to brake, you're at the point where only the right front tire maintains any effective contact with the pavement, and the car pivots. End result, a nice donut. Chances of this scenario increase with rain soaked pavement, not to mention the grease and oil of a well traveled highway.

IMHO, our factory shocks do not have the longevity we may expect. I believe our tendency to enjoy the handling features of the MM wear them out sooner. Shocks serve to dampen (delay) body roll and as shocks wear, this control diminishes, but you don't always notice it until something like this happens. If your MM has 20K miles or more, I suggest you inspect your shocks, I'm willing to bet you have been driving on springs and air suspension benefits more than you know. I replaced my shocks with a fresh set of OEM shocks at 12K miles, and I was surprised at the difference. There were no performance options for shocks back them (thank you QA1), but the difference in refreshing them was alarming.

If you think about the dynamics of this hard left turn with fresh tires, the left rear shock may be showing it's wear in allowing too much extension too quickly, while the right front shock likewise allows too much compression. Both increase weight transfer and build inertia, which accelerates loss of control.

Tire PSI was mentioned ^ there, and IMHO, tire pressure is misunderstood. Most of us talk about PSI in terms of maximizing tire wear. However, IMHO, correct tire PSI is about finding your ideal rolling resistance and reducing that as much as possible, and no two Marauders are alike. Anything less that 30 PSI on a car this large and heavy is dangerous, sidewall integrity will not sustain the weight of the MM in hard cornering and the tire will roll under. Maximum PSI is stated on the sidewall, but realistically it's probably in the range of 40 PSI. Any higher will leave the tire too "hard" and traction will diminish. Somewhere between 30 and 40 PSI is your ideal PSI, and if you can dedicate an hour of your time explorig this, you may be pleased with the results.

Inflate all four tires to 40 PSI and go for a drive. Speed isn't important, just bring the car to a point where it's pulling it's own weight, and coast. Try starting at 30 MPH and coast to 20 MPH, measuring your time and distance traveled. Then reduce PSI a pound at a time, test again. Somewhere along the test, you will see your maximum coast time and distance traveled, and that's your ideal PSI for your MM. Stick with it and you'll get your best MPG, tire life, and control. Correct PSI will be different for every car, find yours?

Anytime we make any changes to our control systems, i.e. brakes, shocks, air suspension, tires and such, we need to spend some seat time exploring the car's new handling features. I've driven a dozen Marauders at local meets, and no two Marauders handle the same. When you change something, you need to learn the new limitations.

Again, glad you and your MM are okay.

[bigslim]

I've heard of this happening before. Factory workers mixing their own urine into the tire creation process... It is a sad day when you can't but a set of tires without some union pee mixed in to ruin your traction. I'd head straight to the production floor myself! Good luck with your urine slicks
Let's not knock the union now, "OK". :mad:

[duhtroll]

Mine are great in the rain - it's been raining nearly nonstop here for a week, and even in the monsoon that was last Friday, I had no traction problems at 75 MPH on the highway.

I'm not trying to be insulting, but these are directional - you did put them on with the arrows the right way, right? It could happen.

-A

[Smokie]

I've taken this turn many times with the stock KDW tires and have not had a problem. :alone:First I am glad that you are ok, it is good and well that you made us aware of your experience and I don't take it lightly. My experience in the rain with the KDW2 is positive and I have no problems to report, I maintain my tire pressure at 38 psi cold, at all times.

I drive in the rain like if I paid $10 for my tires and always expect the worse, rubber slips when it's wet and when it's cold....no matter what tires you have. The best thing from this is that you have learned something very important about your car's handling and you didn't get hurt or mess up the car...thanks for the heads-up.

[Rider90]

Yes they are pointed in the right direction. My only point is that the stock KDW handled this turn at this speed under the same conditions many times without a problem. Both the KDW and KDW2 are/were at 40 psi, all my tires are at 40 psi and always have been for 5k now.

[BillyGman]

Yes they are pointed in the right direction. My only point is that the stock KDW handled this turn at this speed under the same conditions many times without a problem. Both the KDW and KDW2 are/were at 40 psi, all my tires are at 40 psi and always have been for 5k now.Perhaps some tires will not be negatively effected byan air pressure as high as 40 PSI as other tires will be. I still don't understand why you run such a high air pressure in them. i've never heard of any manufacture recommending 40 PSI, and I don't see what the benefit of running it at that would be other than perhaps gas mileage being better to a miniscule degree which wouldn't even be worth it IMO, and if you were that concerned about gas mileage, then why even have such a heavy car like a Marauder?

[Rider90]

-POST DELETED-

[BillyGman]

I'm not concerned about gas mileage, but I like the firm ride at 40 psi and the way she handles at 40 psi. I've had the stock KDW at 35 psi for 10k and it wasn't wearing well at all. I boosted it up to 40 psi and its like I paused time. The fronts are now wearing evenly across the tread. Since I only have a few thousand miles on the KDW2 tires I am still experiementing with psi to see what will wear better and thus far 40 psi is working out well.Thankyou for that explanation. I guess you should try 32 PSI inwet whether around that same turn as well as a few others to see what happens, because it might be a kind of thing where you just can't have it all. It might be a matter of better handling at highway speeds on dry pavement along with less tire wear too with the 40 PSI, OR better wet pavement traction with the 32 PSI.

[Rider90]

-POST DELETED-

[dflynn5]

I think the missing link here maybe how the roads are built. i.e. the materials used in harsher climates. I lived in Ontario, Canada for a few years and the roads were absolutely treacherous when wet. Any type of power applied in a corner in a rear drive car would cause the back end to break loose. Breaking was also nerve wracking. By contrast, in California I have much better grip when the roads are wet. I'm excluding the first rains here because after a prolonged dry spell, the build up of rubber and oil and then rain does not make a good combination.

[ctrcbob]

SergntMac,

You say you have Pirelli tires on your MM, however when I go to the Pirelli website, they say that they do not have any tires for the MM.

What model Pirelli's do you have, and what size?

[Donny Carlson]

I've heard of this happening before. Factory workers mixing their own urine into the tire creation process... It is a sad day when you can't but a set of tires without some union pee mixed in to ruin your traction. I'd head straight to the production floor myself! Good luck with your urine slicks
Man, the Fisher clan slays me.:D

[Murader03]

Boy, am I glad to see Sarge back. I missed his explinations and the one above makes interesting reading as do most of his posts. Now to go do something with my shocks........

[SergntMac]

SergntMac, You say you have Pirelli tires on your MM, however when I go to the Pirelli website, they say that they do not have any tires for the MM. What model Pirelli's do you have, and what size?
The Pirelli site can be difficult to navigate, they spend a lot of time on tires made for specific vehicles. You can locate them by size at Tire Rack, or one of the other large distributors. Fronts are 255/45/18 and the rears are 285/45/18, P-Zero Assymetricos. No problems with fitment, but you'll need a wider wheel in back. They are pricey, maybe as much as 20 percent more over compatable tires, but the ride and control is the best I've ever experienced. Grippy sticky beyond your imagination, and I get a lot of compliments on the profile.

http://www.mercurygallery.net/mmnet/showphoto.php/photo/8157/password/d746d272dfed711f349d5453ed3b71 f7/sort/1/cat/500/page/1

[MarauderMark]

The Pirelli site can be difficult to navigate, they spend a lot of time on tires made for specific vehicles. You can locate them by size at Tire Rack, or one of the other large distributors. Fronts are 255/45/18 and the rears are 285/45/18, P-Zero Assymetricos. No problems with fitment, but you'll need a wider wheel in back. They are pricey, maybe as much as 20 percent more over compatable tires, but the ride and control is the best I've ever experienced. Grippy sticky beyond your imagination, and I get a lot of compliments on the profile.

http://www.mercurygallery.net/mmnet/showphoto.php/photo/8157/password/d746d272dfed711f349d5453ed3b71 f7/sort/1/cat/500/page/1


New shocks (QA1 i saw that thread too), new tires(Pirelli's) w/ widen rims , and check the tire pressure.Yeah a little pricey but it sounds like this is what i want ..Thanks Sarge for the info...:up:

[SergntMac]

I just read this in another thread here.

255/55/18 KDW2 Tires (Rear): A much better improvement over the stock KDW tire in dry traction and handling. A little is to be desired in this reviewer's mind when it comes to wet traction, but in any case you shouldn't be driving like a maniac when it is wet out anyways.
Rider, I'm not flaming you, or, calling you out to get flamed, but the KDWS that come OEM and the KDW2 that we speak of here, are remarkably different tires. Different tire compound, different tread pattern, and very different handling features, i.e, traction.

IMHO, it's not good to mix such radically different tires with each other, and if you have the KDW2s on the rear only, (as this other post indicates) I'm not surprised at all that the back end came around on you. In fact, I'm surprised it's only happened twice. Your traction capabilities are decidely unbalanced front to rear, and this directly affects your ability to maintain control in hard cornering. It magnifies lift and diminishes grip in much steeper terms than I described ^ there. It's as good as driving on a flat.

Most manufacturers will caution you against mixing tread design, unless you have a specific (and temporary) intent in mind, such as drag radials on race day. I've had my own experience at this too, with MT ET Streets at the track, not fun. The manfacturers are not wrong, or, just trying to sell a full set of four. Please look into this?

[MENINBLK]

If you are finding that your traction is NOT where it should be,
why not post a complaint in the BF Goodrich Tech Talk Forum ? :dunno:

They only Manufacture the tires.
http://www.bfgoodrichtires.com/bfgapp/servlet/Controller/site.forums.LoadTopic?topic_id =.1dce8370

[Rider90]

I just don't see why my traction would increase in the rain if I had these tires up front as well. In fact I would probably be worried.

Here is a good one:
http://www.bfgoodrichtires.com/bfgapp/servlet/Controller/site.forums.LoadMessages?discu ssion_id=.1dced6f1&topic_id=.1dce8370

Pete, do you even have those tires? ;)

UPDATE: Just read a post on there about tire temps, maybe I spun around so easily because it was 45-50* out? Maybe the rubber got a little harder than what they made it for and adversely affected traction in the wet weather.

[SergntMac]

At your suggestion, I did some light reading at the BFG site, and Tire Rack as well. Sorry to say, Rider, IMHO, your experience stems from mis-matched tires, front to rear.

Each tread pattern has it's own unique way of processing water, and it's own treshold before hydroplane. Each has it's own unique wet pavement qualities, thus, you may expect one end of the car to react to rain, standing water and hydroplane, before the other end. With 80 percent of your braking power in front, different thresholds, and no change in your driving habits, I see no reason to question, or, blame the manfacturer.

The KDW2s have been around a while now, they are a great tire for the Marauder, and many members here are quite pleased with them. Why not buy 2 more for the front, test, and then offer your opinion? I'm sure it will change. BTW, here another thread discussing mismatched tires, happy motoring.

http://www.mercurymarauder.net/forums/showthread.php?t=17734

[Rider90]

Sarge, for the sake of internet arguing, I'm just going to rest my case. I do not have the knowledge or experience you have as I'm sure you've already figured out. I will leave this thread still not understanding why using two different tire designs front and back, will result in the back getting horrible wet traction in comparison to the old rear tires under the same conditions. Even looking past the fact I was taking a turn, I was still going at a cautious speed and most importantly at the rate of the 6 or 7 cars surrounding me in two lanes, none of whom spun to the side like me. Weight differences, distribution differences, there would be so many factors it would make me sick. I do though have an extra 100 lbs in my trunk due to the Amplifier and Subwoofer.

The first time I got upset at these tires is the one I never explained. It was simply a test of the tires in a straight line. At a stop light I got on them until they, on purpose, broke loose. The plus side is correct what everyone says, it tracks very straight and does not move over. The down side is I've accelerated faster with the worn out OEM tires in the rear and have not broke them loose as quickly as I did these.

It just dawned on me. Rather than deleting the above paragraph, I thought I would let you know about the mind-set I am in. Silly me, I installed 4.10 gears at the same time. I feel like an idiot and this will explain the difference in acceleration between stock OEMs in rain the KDW2s in rain. Well it is better to understand the mistake and correct it than proceed in the path of foolishness.

In this person's mind though, I am still a little worried about the rears, and the hairs still rise on the back of my neck when I am on the freeway driving on slick pavement. I do not think I will get the fronts as the same tread unless I am thorougly convinced that is where my problem is.

I'm sorry for taking up your time, and you might actually have to meet me at the Chicken Run ;)

[SergntMac]

I apologize if you feel we were arguing, Rider, I thought I was helping you solve a problem. Granted, it would have been better if we had known the full circumstances of you situation from your first post, there's a few posts following that (including mine) that are misdirected for lack of information. However, I assure you that I am only trying to find an answer along with you.

Once the question was raised, it's in everyone's best interest to find the most correct answer. The tire in question is an outstanding product many of us enjoy, but it's new too and if use in the field reveals shortcomings, all of us (and the manfacturer) should know it ASAP. I see it as our responsibility to rule out the possibilities of "pilot error" before we damn the product, the vedor, or, the manufacturer. Fair is fair, yes?

I'm no smarter than anyone else, but I do take advantage of resources. Here's one for all from our friends at Tire Rack. It's nice to see this brand independent 411 available to us. There's a hundred topics on tap, and an interesting link at the bottom.

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=16&currentpage=1

I tend to illustrate my opinions in ways that displease a few, but I'm not just speaking to you, or, any other single member. I'm speaking to all readers, and illustration is helpful in getting my point across. Still, others do misunderstand and sometimes, I misunderstand them. Absent malice, it's no big deal. But, I feel it's better to keep at it, than giving up. Without an answer, what good does the question do any of us?

At this point, Rider, you have your checklist of possibilities to rule out before drawing your final conclusion, and I hope you consider my opinion as well. Still, if the bottom line is that you're just not comfortable driving on the KDW2s, then you should know that I agree with you without reservation. Having confidence in your selection is ultimately the first, and last concern.

IMHO, case closed...Next?

[Rider90]

I'll "play" around when it gets wet late at night and really get the attitude of these tires. Not saying I'll be driving all over like a maniac, but I will most certainly be in the very large Menards parking lot driving around, stop and go, and acceleration through turns as if I had just got my learner's permit. I think I am a great driver. These tires have made me feel the need to rethink the characteristics of my car and honestly it is something I should have done the first day I bought them.

I still think the OEM tires did better in the rain, even though I thought they weren't all that great either. Best Wet/Dry tire I ever purchased were four new Michelin Pilot Sport A/S tires for my 99 Crown Vic.

Case closed, this thread has reached it's end and then some.

[metroplex]

BFG anything sucks in the rain, especially if they're not brand spanking new and even then it's iffy. Just look at the piss poor tread design. BFG treads were obviously designed for mainly dry pavement driving. If you had 17" wheels I'd recommend the Kumho KH11s.

[Rider90]

BFG anything sucks in the rain, especially if they're not brand spanking new and even then it's iffy. Just look at the piss poor tread design. BFG treads were obviously designed for mainly dry pavement driving. If you had 17" wheels I'd recommend the Kumho KH11s.
What would I do without your insight, Charlie :rolleyes: