2013 Sierra HD, is a gear change worth it?
Hi everyone, I'm new to this forum and have a question about my 2013 Sierra 2500 HD with a 6.0L and 3.73 gear ratio. It has a tow rating of 9400 lbs and in the manual it says if I had 4.10 it goes...
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The tow ratings need to cover nearly any condition, including launches on extreme grades. Just lock it out of 6th on the flats and let it spin on the hills. It will still run approximately the same RPM with lower gears because it still has to make the same HP (although the gears would be more closely spaced to allow finer RPM adjustments).
At 3500RPM and close to 380 ft-lb, it's making 250 HP which is approximately enough to keep a 16000 lb truck/RV rig at 60MPH on a 6% grade. You should only need around 100 HP to keep it at 60MPH on the flat so ~2200RPM(I think that's where you'd be in 5th) would be plenty with the 6.0 TQ curve. Running 6th gear, you'd be making just over 100HP so it is likely to hunt. That's where the diesels shine. Just a little boost, 800 ft-lb and you're over 200HP in a heartbeat.
At 3500RPM and close to 380 ft-lb, it's making 250 HP which is approximately enough to keep a 16000 lb truck/RV rig at 60MPH on a 6% grade. You should only need around 100 HP to keep it at 60MPH on the flat so ~2200RPM(I think that's where you'd be in 5th) would be plenty with the 6.0 TQ curve. Running 6th gear, you'd be making just over 100HP so it is likely to hunt. That's where the diesels shine. Just a little boost, 800 ft-lb and you're over 200HP in a heartbeat.
