Quick introduction: I have a 2019 Chevy Silverado LT. The truck has Camburg UCA’s., King IBP 3.0 coil over front shocks, King IBP 3.0 rear shocks. Deaver leafs springs, 35” BFG, amp electric steps, and quite a few other additions to the truck.
I wanted to post about my recent experience with re-gearing my truck. Hopefully this will help somebody somewhere because the information that I tried to find is extremely limited.
My gear ratio was 3.23 and I went to 4.56. The company that installed the gears originally put a Hyper-Tech in-line speedometer and gear calibrator on the truck. It worked fantastic driving around town, but once I broke the gears in, I started driving and on the freeway. While on the freeway doing 79 mph I got a notification on the dash that stated truck is governed at 92 miles an hour. Then the throttle was dead (governed) Keep in mind my speedometer was dead on with GPS. I spoke with Hyper-Tech about this and they stated it’s potentially too big of a gear change. They only know of the in-line calibration working up to 4.10 gears. (That is not confirmed).
Something in the rear end wasn’t talking with the computer in the front end so I bought an edge pulsar LT in-line calibrator thinking that that would work better. I ran into the exact same problem except the governor was now set at 112 MPH (which is the stock setting on that truck). But at 85 miles an hour my driveshaft felt like it was going to detonate. Basically the rear end was turning the driveshaft RPMs as if it was doing 112 mph.
I finally found a company that re-geared a 2019 Chevy Silverado with 4.56 gears and they ran into the exact same issue. The way they ended up fixing it was the truck had to be tuned not performance tuned just tuned so it accepts the new gears.
I’ve been dealing with this problem for about a month now and I finally caught a break two days ago and received that information and had the truck tuned and it drives absolutely perfect shift. Perfect. Everything is like stock.
Hopefully this helps somebody looking for some information. I don’t know if this applies to 2022.5 and up I just know specifically it applies to 2019 through 2022 pre-refresh.