BFGs ATs vs MTs for sled pulling

Sorry to start another tire thread but this is a bit different. I am currently running a 3rd gen Dodge nv5600 with approx 700hp. Currently run in 4 low and 4th with 33x12 BFG AT.

Most of our tracks here are clay but moisture content and time of day play a huge part. Some times the tracks are very tight at night but daytime pulls will be looser. This year I found I didn’t have as good of traction and lost to some trucks I know carry less wheel speed down the track than I do, when the track was loose. I do have a front locker just to clarify.

I am thinking on bumping up to 35s this year and debating on going with KM3s instead of the KO2s. Reason I want to stick with BFG is I get substantially better deal on tires from BFG then anything else.

I haven’t heard of many people running the BFG MT and wanted to see what everyone thought? I was thinking on giving them a try but I had a set of Cooper STT pros a couple years ago in a 33 and didn’t find they hooked very well.

Gear ratio?

Sorry thought i had put that in the original post. still have the factory 3.73s. i do have a spare set of 4.10s laying around as well.

truck normally pulls 4000-4200 down the track, dips down to probably to 3700-3800 at the end of the track. Currently run with the 33 ATs around 50 psi in the rear and 20-25 in the front.

I have some thoughts but my first question is why are you running in 4th gear as opposed to 5th and a 1:1 drive ratio in the trans? I think 4th is 1.39:1 and your transfer case is is a 241? so it's 2.72:1 so your final gear reduction is ~14:1? At 400rpms your wheel speed is ~28mph?

If so, I used to run a daily driver 3rd gen that was around 775hp at the wheels with an auto 1:1 and 2.72:1 transfer and 3.73 gears at 3000-3200 rpms (~29mph) down the track.

I ran 33" tires and mud grapplers with no problems, having said that if you are running in 4th gear to stay on top of the charger, I would stick with AT.

I can pull 5th on a couple tracks if they are real loose but I couldn’t get away with most of the tracks in fifth. Auto is a bit different as you can shift and you are already moving instead of trying to come from a dead stop in 1.1.

There seems to be a lot of work stock/open street trucks running pretty fast final drives with good success from those I’ve talked to. I don’t pull on tacky clay tracks so I might be talking out of my ass but might it be worth trying to make the power to run direct with 33’s? I’d be hesitant to make the jump to a larger/more aggressive tire if I didn’t have enough power to run direct as is.

Jervis said:

I can pull 5th on a couple tracks if they are real loose but I couldn’t get away with most of the tracks in fifth. Auto is a bit different as you can shift and you are already moving instead of trying to come from a dead stop in 1.1.

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I've pulled with a NV5600 before as well and always pulled in 5th with a 35" tire but ran A/T's and 4.56 gears. If you can't pull in 5th than I would definitely stick with A/Ts and change your gears. Ideally pulling in 5th with a NV5600 will help it live forever give you better results on the track.