I've noticed on several occasions where I try to launch on wet pavement (while it is raining for example) that the car exhibits severe axle hop when it is not getting any traction. It happens in first gear and second gear at sub-3000 RPM. The entire rear of the car starts to vibrate badly. The only time I have encountered this on another RWD car is on my 2000 Crown Vic but only when I lose traction in reverse. The Vic has a stock Watt's Linkage rear suspension.

My 07 GT did this before the Hellwig rear sway bar, so I don't believe the bar has anything to do with this.

Any ideas? Is it just the inherent design of the S197?

 

This is very common for our cars and can be easily addressed. It is usually resolved with aftermarket LCA and or UCA with poly bushings. I would start with some LCA's as they are the easiest to install.

 

Which lower control arms come highly recommended? My goal is to keep this GT totally streetable, be able to go on a long road trip with a girlfriend and not have to explain/justify why there is so much vibration yet make it corner-worthy.

 

You can't go wrong with any of the major brands with poly bushings including Steeda, J&M, UMI, etc. I run Steeda billets on mine with no noticable increase with NVH.

 

What about the Ford Racing arms?

 

Well I saw a 2011-up 5.0 GT at work, and checked out the lower control arms. They are of a different stamped design, but still stamped and not boxed/tubular. I think I'll just keep it stock.

 

I had the same issue on my 2010 GT so I ordered a set of J&M Lower Control Arms...Installed them yesterday....no more hop, and snap oversteer in corners is gone.

Huge improvement.

 

How is the quality on the J&M bar set? Did you notice any extra noise or vibration going into the cabin from the new bars?

Did you feel any change in the handling?

The only complaints I have is the axle hop when I lose traction while trying to accelerate in a straight line, and the car jumping all over the place sideways when cornering fast on a bumpy surface.

 

If I were you, I'd get the boxed LCA's. at $200-300 they're relatively cheap, and they'll make a world of difference. I never saw any NVH increase with my BMR LCA's.

It was the Steeda adjustable upper control arm that added significant NVH (makes sense because it connects to the underbody right under the rear passenger seat. Kind of acts like a big stethoscope.

 

Quality is excellent. I sent them an email question today and they answered back within an hour and suggested I call them. Got a real person after 3 rings, was the guy who emailed me...he answered my questions on the spot. Excellent support IMO.

There is extra noise and some vibration, but the stability in the *** end is well worth it. I went with the "less extreme" LCAs. I also installed their camber plates.....HUGE improvement on the front end.

 

I did not find any additional NVH in the Steeda adjustable upper control arms, in fact it stayed about the same. DId you put the full competition version on? This will definitely increase your NVH.

I have seen vast improvement over the wheel hop that i encountered previously. These control arms were a little bit cheaper than the ones you have mentioned and are just as good!

Do your research and you fill find not many control arms stand up to the Steeda brand. This is the website I used when determining my upper control arms.

http://site.americanmuscle.com/solidcactus/reviews/viewall-new.php?theid=steeda-adjustable-controlarms-7904&thename=Steeda%20Adjustable%20Street%20Rear%2 0Upper%20Control%20Arms%20(79-04%20All;%20Excludes%2099-04%20Cobra)

Just to give you some more insight.

 

I got this one:

http://www.steeda.com/store/steeda-a...d-mustang.html

It's not horrible, but it's a noticeable increase in NVH. Granted, that was the last in a long line of suspension mods I did. everything else in the rear was replaced before that.

 

I had the J&M on mine for over a year. Big improvement for the axle hop with just a slight increase in bump jar but there is always a trade off. I took them off however because when I went for a ride at -35*F, the grease did not work and the rear of the car sounded and felt like it was going to tear apart. That's why OEM uses rubber bushings instead of poly.

I was actually thinking of trying only a Roush upper control arm as they've modded the oem with a smaller rubber bushing that's already used for the diff's end support. That one should be better for winter use. The only reason I didn't try it was I feel it's way overpriced.

 

Did you use our poly bushing version? Cause that one does not significantly increase NVH by itself. If you combine it with poly bushing lowers, the 2 combined may increase NVH slightly, especially when combined with a different brand of arm that is going to have a higher durometer bushing on the lowers than ours. You can see an increase in NVH if your pinion angle is off as well.

Our Steeda billet lower arms are dead silent by themselves and combined with our poly bushing uppers would hardly be noticeable from stock, especially with other modifications such as an axle back that would be louder than anything else.

 

SteedaGus:
I noticed Roush only uses a revised upper control arm to eliminate wheel hop. What is your recommendation for the simplest approach to eliminating wheel or axle hop on a S197?

Do I need the revised lower control arms, or will a new upper control arm fix the problem? Is the problem related to pinion angle, or flex from the arms?

I crawled under some 2011-up 5.0 GT's here and they all still use stamped control arms, with slightly different indents but not nearly as stiff as a tubular/billet arm.

 

When I got my S/C about 4 years ago I put the Steeda lower control arms on and that got rid of my wheel hop without adding any NHV that I could tell. Last year I added their Competition rear upper 3rd link and again I didn't get any noticeable increase in NHV ...

 

Roush has billet lower arms too. Not sure who is pushing just their upper, but they do have billet lowers that are meant to improve power transfer and reduce wheel hop.

 

If you go on their web site, they have an Anti-Wheel Hop kit with just the upper control arm and a weird cowl bracket.

So is the Steeda billet lower control arm better at killing wheel hop versus the Steeda tubular lower control arm? Why hasn't Ford done this at the factory? I see their 2011 5.0 GTs still using stamped steel arms and owners complaining about wheel hop.

 

It's all about the bushings apparently. That's where the vast majority of the flexing comes from.

 

I've got UMI's roto-joint/poly LCAs (roto-joint is a fancy way of saying plastic spherical bearing) and I didn't notice an increase in vibration, just ride harshness when it came to going over bumps in the pavement (like missing chunks of asphalt and/or sections of concrete with noticable edges and elevation changes). Otherwise not bad.

I'm not endorsing UMI over any other brand, just relating my experience with thier hybrid control arm.

I combined the LCA with relocators because I was experiencing severe wheelhop on the Shelby, especially when the weather turned cool and it approached 40 degrees. It was bad enough that I thought the loadng and unloading would ultimately tear the rearend up.