Pre Checks
1. Check tires for proper inflation and condition. Classic - 28 psi front, 38 psi rear COLD Discovery - 26 psi front, 36 psi rear COLD2. Check road wheel balance.
3. Check suspension bushes, shocks, etc. Correct any problems.
4. With gearbox in park / neutral and parking brake set, slowly increase engine speed until it reaches 4000 rpm. Correct any engine vibrations.
NOTE:
This diagnostic chart assumes that the source of vibration is NOT engine related.
5. With the road wheels on the ground, visually inspect the universal joint angles at the front and rear differential. The rear driveshaft should be nearly in-line with the differential pinion. The front pinion should be slightly "nose up." If a universal joint angle is grossly incorrect, it must be corrected before proceeding.
NOTE:
EAS equipped vehicles must be at standard ride height.
6. Inspect the driveshafts and parking brake drum for excess undercoating overspray. Remove any accumulations before proceeding.
7. Inspect condition of driveshafts. Replace damaged or bent components.
8. Inspect for any fouling between engine and body. Confirm that transmission dipstick tube is not against the firewall.