Check your pinion angles. If you're not having an issue, i suspect one of two things:

1) Your u-joint is in great shape... and you'll eventually have an issue

or

2) You're running aggressive tires and don't realize you're having an issue yet.


Mark (lekmedm) recently had a SL 4" installed, standard height, and asked me to check out a few issues he has noticed since the lift install. Most concerning to me was the drone sound he had at highway speeds, especially with light throttle applied. I knew it was either his pinion bearing or the u-joint.

Well, regardless I was not happy with the pinion angle from the SL install. So whether that was the cause of the noise or not, in my opinion it needed to be corrected. He ordered new upper control arms from Rustys Offroad earlier this week. By skipping the powder coating he was able to get them on Friday and we put them in today.

The new arms (pictures below) corrected his pinion angle and eliminated the drone noise. I'm yet again disheartened at the fact that a company like Superlift would miss something like this. Looks like when im ready to put on my 4" kit I know of a guaranteed $240 addition to the kit (unless superlift fixes it in the mean time).

Some pics of the new Rustys arm and before/after pinion angles: