New gears for 35's?

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panda24619

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you dont need new gears but its recommended. idk how to exactly change the gears but i think you disconnect the drive shaft. drain the oil. pull out the diff. and swap the gears and bearings. then put it back in with the correct oil. while your at it change out the axle shafts. i've read that the shafts are the weakest point in these rear ends.
 
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Marvo75

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What do you mean by dont need em? Wont the speedo be off like crazy at highway speeds? I know how to change the rear diff gears..NOT FUN! Do most just run it with 35's and say screw the gears?
 

tonydiv

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If you jump up to 35" tires you will notice a major difference in the get up and go factor. It's not to say that you can't just go ahead and do it, but you just need to be prepared for the lack of power and reduced mileage. Also you'll need to keep a better eye on your speed, since the speedo will register 5 or 10 miles slower than you are actually going. My speedo is off by 10%.

My truck has 3.73 gears and I really want to toss in a pair of 4.10 or 4.30 gears.

The new gears will fool the truck in to thinking that you have standard size tires on it. The mileage will improve and the truck will drive better since it will shift gears at more appropriate times.

Around town I don't really mind it, but when I'm on the highway, the truck will downshift out of overdrive every time it has to climb a hill. I also notice it alot when I'm towing the boat.
 
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panda24619

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so yes for the most part people just put the 35s or 37s like walnuts has and just goes.
 
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Marvo75

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I do a lot of highway running so better pass on the 35's till i get the money for new gears. Thanks for the info guys really...
 

panda24619

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yeah any time. if you do mostly high way driving gears are what you need. if you have a4wd full time or if you use 4x4 a lot then you will need 2 sets. other wise if its 2wd and you never use 4wd then just get the one set till you need the front set.
 

tmajikman

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yeah any time. if you do mostly high way driving gears are what you need. if you have a4wd full time or if you use 4x4 a lot then you will need 2 sets. other wise if its 2wd and you never use 4wd then just get the one set till you need the front set.

If its 4wd, you have to do both, even if you don't use 4wd, it will destroy one or both gear sets if you don't.
 

walnuts4x4

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pssshhhh who needs gears.... still running the stock 3.73 with the 37s and not doing too bad even towing my boat.... but the edge programmer made a huge difference and while not like having gears it is helping a lot... when I get the funds I will either be doing 4.56 or 4.88... had 4.88s in my old 97 f150 with 38x15.5 swampers and a 4.6 but still haven't decided on which to put in my expy with the 5.4.... but a cheap "band-aid" fix to power and speedo (well 99+) is a good quality programmer
 

panda24619

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SUPER easy. the edge like he has is a plug in style that stays plugged in. mine is a flash programmer. plug it in let it do its thing and throw in the closet till you put it back to stock and sell it. haha you plug it into the data port under the dash on the drivers side and answer a few questions and it reprograms the motor. thats how it is on mine. on the edge you plug it in and answer a few questions and you can change settings change how the truck runs and what not. really fun to play with. but his is costly. i got mine for $100 off craigslist.
 

walnuts4x4

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yeah the edge CS is a couple of bucks mine was $350 but as was said it plugs into the OBD2 port under the dash then route the wire under dash and around by the door till it gets to the top of the dash then either a suction cup mount (like GPS) or a gauge POD that attaches to dash....

then you follow the on screen questions such as tire size and gear ratio then select your program mode... also while it is plugged in you can see up to 8 different parameters of you engine from MPH, temps of tranny or cylinder head, air temp to intake, % of throttle position and tons of others.... best bang for your buck unless you find a used programmer.. plus edge can be upgraded by company's like PowerHungryPerformance and they make custom tunes exactly for your engine setup...
 

Bart Man

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Grearing and Programers

Hey Gents how are you all !,Its been a while and here is my situation, I have the Edge Programer and it does make a huge difference in shifting and acceleration, it also compensates for tire size and gearing! I would like to know what the best size gears would be for me , anybody know any good sites to calculate?? Tire / RPM / MPH , I'm getting about 12 MPG , I not complaining but I want a little more get up and go, and if it helps my MPG then great!
 
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