I have a 2006 3.7L V6 Dakota Quad Cab. I put 265/70 BFG KO A/T tires on it and now the engine seems sluggish. It was recommended to me that I should get new gears for it to put a little more get-up-and-go back in my truck. However, I know very little about gears and don't know what size to go with or even if I should be looking to gears to fix my problem. Please help!!

 

If you're 4wd, you will need to change both front and rear gears, that gets pricey. But as far at 4.10 or 4.56, it really depends in your preference. If you are looking for fuel economy, either gear ratio will help your overall city mileage, and hinder your freeway mileage. If you do more city than anything, you will see an overall gain, better gain with 4.56s. If you do mostly freeway, you will lode mpg. More so with the 4.56.

Now if none of that matters, then 4.56 will give you the highest gain in torque, and the biggest change in driving characteristics. You might even be able to peel out with 4.56s on that lethargic v6.

Its costly though, parts and labor for 1 diff can run you 500-1000. Add a front diff into that and its 1000-1700 smackroos gone in a blink.

 

Yea, I figured the price would bite me in the butt in the end. But I just can't handle the sluggishness of the large tires on top of the less powerful v6. I do a lot of freeway traveling so I'm not sure the 4.56's would be the best. But would I still see a significant change with the 4.10's? If I am going to be shelling out a couple grand I want to be sure it is worth the money.

 

$200-$300 or more per gear set (good gears are not cheap; bad, noisy gears are cheap), $100-$200 for master install kits for both differentials, $400-$600 in labor per axle. Even if you get all the best deals in the world, you are still looking at $1500 as a bare minimum, probably closer to the $2000 mark.

Kind of funny when you think about it... the higher gear ratio option when buying a new truck is usually less than a few hundred dollars anymore. Soooooo much more to do it after the fact.

 

If you have 3.92s stock, then 4.10 won't be worth it, but if you have the 3.55s then you will certainly notice a difference. Whether its worth it or not is really up to you, but with big tires you may find yourself at around the same mpg freeway and only slightly less with the 4.56s. It will certainly have you maintaining gears longer in hills without downshifting, and maybe help turn those wheels good enough to lessen the mpg hit. So is yours an auto or manual, and 4x4 I assume?

 

Oh, and then there's the shops that will want to rebuild your axles when they open it up. They may be right, they may be trying to con you, but there may be additional expenses.

 

Yes it is a automatic 4x4. And I don't really know what gears it came stock with. I assume something like that would be in the owner's manual?

 

For the kind of money it will cost to switch out the gears in both axles (b/c of the 4x4) would it be better to look around for a used 4.7l v8 engine and swap the engines? Would the 4.7 fit in my truck? What modifications would be required to accomplish a swap like that?

 

The purchase of motor mounts probably, wireing harness, pcm for sure.. Most everything else remains the same. I think the fuel pump is the same, radiator.. Perhaps the drive belt accessories are different. Oh and the transmission is the smaller 42somethingsomething if I remember right, whereas the 4.7 has the 545rfe. Lookin at 4000 or more to do it right, minimum. Then you'll want gears after that haha.

 

Oh Wow... Well I Guess PuttingInTheGears IsStillThe Most CostEffective