I have a 1990 4matic 300 E which i love. 95,000 miles mint condition, except the vibration in the front end at low speed turns. I replaced both inner and outer CV joints both sides because the boots were ripped, thinking this was the problem- nope. i got sick of hearing the problem, so i thought i would flip the " test" lever to test. Low and behold the noise is gone, and the vibration. It finnaly drives like a 300E should, smooth and quite. So i know its a 4matic issue. Mechanic said it could cost me thousands just to find the problem. I guess i will drive it like it is till winter, and then i will flip the lever back in the normal posistion. Any ideas?