Hello,
I've been trying to find out what the source of the instability when driving down bumpy roads. I thought it might be a suspension component (watt's linkage). It was suggested that tires may be the problem. A rear tire was 10 psi low. I hadn't checked it for over a month and probably damaged the sidewall from some aggressive cornering. Tire center checked in water and no leak. That means air is escaping during driving. I noticed that more air escapes the more aggressive the driving (for some reason I've never experienced this type of problem before). These are Michelin energy LX4 on an
04 Town Car. The car was bought used at 36.5K miles in Feb 07 and I didn't put the tires on. They're dated 43rd week of 06. The TC now at Oct 07 has 44Kmiles. The tread are ~1/4". Michelin said I should have a tire removed and inspected for damage. I tell the guy at Sears to do it and he looks at the tires and says it's something else - didn't see the need to look inside.Struts and shocks were replaced with KYB (551600 strut, 551601 shock in 07 cat.) and front end aligned. No loose suspension components were detected, even after several inspections at various places. Problem still exists. There's that irregular lateral movement over bumps. Shocks have nothing to do with lateral motion. It was never there until a few months ago.
So maybe I should get rid of these tires and consider what they put on a CV interceptor. Hell, I already ruined that "Town Car ride" with KYB urethane strut and shock mounts, which only made the bumps more noticable, but didn't help cure the problem. Why not just change to some less comfortable tires that have more durable sidewalls.
It doesn't make sense. I called one limo/livery service at random and the mechanic says they just go to sears and have michelins put on - didn't say which model though. So, I have 44k miles and those livery cars go 200k-300k.
The new dampers and mounts apparently increased city mpg from 16.2 to 17.4. Big-O tires decided to set the fronts to 35psi. The sticker says 32 front 35 rear, but Big-O says it's for the "dealer ride". That's comical. I suppose Ford has the sticker just for the test drive and the shops know better. The service advisor at the dealer didn't seem to care, however. I guess it's safe to set the fronts anywhere between 32-35.
Thanks for any suggestions
Ben