Looking at getting some 4.10 gears for my 04 Mach. Talked to about 5 different local shops and got 5 different answers. The last guy I talked to(only one who mentioned this) said that the car would surge(speed) and that the speedometer would be way off. Is this true? Another demanded I needed new pinion bearings, etc. Yet another said I could reuse the bearings I had. Installation prices ran from 250 to 500 dollars over the five different places. Can someone please help verify what it takes to put in 4.10 gears, parts, etc.? Any info. would be greatly appreciated. Thanks. Jeff

