Gear change questions?

[KOwens]

Hey TDR gurus,



My buddy is considering buying a 2005 4X4 with a 4. 10 rear/front end gears. I would like to know what problems might occur if he change these gears for 3. 54 to get better mileage. He may tow occasionally but mostly does Home Depot material runs, etc.



What possible problems might occur with the Power Control Module or other engine speed versus vehicle speed controls/parameters on this truck.



Just so you know, I've never done this myself but wanted to get your advice on gear changes and how the vehicle deals with it electronically. Last thing he wants to do is buy an expensive truck and screw it up trying to get better mileage.



Any info would be appreciated.



Thanks Kevin

 

[DGamelin]

If you never have done a gear swap before. I would get help, at the very least you will need a dial indicator to set back lash, torque wrench for bearing caps, and a torque wrench that measures in inch pounds for pinion pre load. Your contact pattern is very important. I think the software changes will be the least of your issues. Also a good idea would be to get a shop manual on that axle, you'll need the specs anyways. I think the smarty will let you change gear ratios in your computer. Good luck and have fun.



04. 5 3500 4wd cc dully 373 6speed 51k smarty

93 2500 2wd xc 354 auto 250k

 

[steved]

Hey TDR gurus,



My buddy is considering buying a 2005 4X4 with a 4. 10 rear/front end gears. I would like to know what problems might occur if he change these gears for 3. 54 to get better mileage. He may tow occasionally but mostly does Home Depot material runs, etc.



What possible problems might occur with the Power Control Module or other engine speed versus vehicle speed controls/parameters on this truck.



Just so you know, I've never done this myself but wanted to get your advice on gear changes and how the vehicle deals with it electronically. Last thing he wants to do is buy an expensive truck and screw it up trying to get better mileage.



Any info would be appreciated.



Thanks Kevin

Swapping gears won't affect anything since the speed is taken from the ring gear.



You will need to find 3. 42s as I don't think there is a 3. 55 for the AAM 11. 50. There is a thread on this forum about a similar gear swap, might check it out.

 

[KOwens]

Thanks for the info guys,



I appreciate your replies. I'll pass this along to my buddy.



Kevin