So i posted the other day concerning my 1999 e55 amg that wants to cruise at 65 and below but nothing faster and have been reading threads about tire size because even my mechanic who is a really good indie here in san antonio is thrown for a loop....if i have new tires which are specified for the car...ie the staggered tire size is correct both front and back and what the car calls for, then why why why am i having issues with my cruise....i would think that if i can cruise at say 65 and all is good, then the system is working correctly....or should i make that assumption....

When the cars computer is reset, how does that affect cruise control?

Lyle in texas

Hi, Lyle.

The tire size issue we discussed previously causes the cruise control to disengage (or fail to engage) because the traction control system perceives the difference in rolling diameter as a loss of traction when the resulting difference in rotational velocity reaches a certain point. The problem you're describing sounds similar, but with properly inflated stock size tires on stock size rims, this shouldn't be the case. I suggest that you take a look at your traction control system, including wheelspeed sensors, to make sure everything there is in order. One question: does the antilock braking system function properly?

Best Regards,
Rob

Lyle, The tire size(s) for you car are: 245/40/18 front and 275/35/18 rear. Is that what's on the car?
Anziani
'97 CL600 53K