New Member With A Drivetrain Question

What's up everyone I'm a new member to this site with a question. I installed 4.10s in my 03 GT over a month ago and I noticed after I broke them in and did some serious driving with them that from 3k Rpms and up I get a vibration that progressively gets worse. Never had this problem with my 3.27s and the car has 130k on it. My question is could the stock driveshaft be over spinning with the new gears meeting it's, I guess you could call it, rotational breaking point? This problem didn't exist till the new gear swap. Thanks in advance for any help.

trinity_gt said:

1) 3K RPM in any gear or in a specific gear?

2) When the driveshaft was re-installed was in installed in the same relative position on the drive flange? Usually there's a chalk mark or a scribe mark indicating the relationship between the shaft and the flange. Check that these are correctly aligned.

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3k in any gear u notice it the most in 4th gear because it take more time to get through so you really notice it.
When I took the driveshaft off I marked the pinion flange an driveshaft flange with a scribe so they went bac together the way I took it out. I did the install before and have installed gears before and never ran into this problem.