So the speedo pickup is at a tire and not in the transmission? Does it use the antilock brakes to calculate speed?

 

Yes

 

Excellent! That eliminates one of my concerns on changing gears to 4.56s.

 

Ramit69 and others, take the advice of the wise and experienced Air Ram, he know's what he's talking about. About a year ago I leveled my truck along with some larger tires. Within minutes of my first test drive I was very unhappy at how sluggish the truck felt (stock gearing on my was 3.73). I noticed a drop in mileage as I drove it (street / highway), and really noticed it needed more pedal all the time. I wised up after reading some posts from Air Ram, ordered 4.56 gears and had them professionaly installed (this is important, gear jobs are easy to screw up). From the moment I first drove the truck afterward I was in love...it was better than stock, I got better mileage, and when I got on it (I tend to baby the truck 99.9% of the time) wow was all I could say.I 100% agree with Air Ram, if I could only do 1 thing to the truck gears would have been it.....for me at least, every truck I own (assuming the trans is geared as high w/OD) will have 4.56's from now on. If I bought one with out the first place I'd stop is the gear shop.....

It's a win-win...just do it ! Get good name brand gears, find a shop who does gears as a primary function (like a good 4X4 shop), break 'em in right and enjoy !