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New Gears!

Jackson76

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Jackson76 Enthusiast

Jackson76

Posted
Posted

Hi Guys!!!

 

I want to know what gears to install on my truck, right now i have the O.E 3.73 and im running on Toyo MT 35x12.50R17

and maybe i would go to BFG MT KM2 37x12.5R17

 

Will i loose MPG with the change?

 

any suggestions? brand?

 

Thanks

2000DV4.8 Senior Enthusiast

2000DV4.8

Posted
Posted

Swapping out gears, if anything, will give you better gas mileage. It takes more work to turn the larger tires, and a lower gear ratio will increase you mechanical advantage, netting you better fuel economy (theoretically). They will also reduce wear on your transmission, which is the main reason to re-gear.

 

With 35s, a 4.56 ratio will be similar to what the 3.73s were with stock tires. If you plan on going larger in the future or want a lot of power off the line, I'd reccomend 4.88s, but keep in mind anything over a 35" tire is in the 'unsafe' range.

 

:)

J-man67 Senior Enthusiast

J-man67

Posted
Posted

Correcto....35's and staying 35's go with a 4.56. 35's then to 37's eventually, or straight to 37's go with 4.88's. Also if you have the G80, well you do....get that out of there too. I'd swap in a TrueTrac!

Majorleaguebass Senior Enthusiast

Majorleaguebass

Posted
Posted

I have 3.73's in my truck...if you want to run 35's good, you need 4:10, if you are going to go to 37's...go with a 4:56, anything bigger than that.....its gonna run like shit, and drive like shit!!!!! Thats what my suspension guy told me and he has been doing this for a long time. if you want to go with 4:88...then you need 40's. Thats the only way that it will not drive like shit.

J-man67 Senior Enthusiast

J-man67

Posted
Posted

He is just saying larger tires on a 1500 is a lot harder on the truck. They weigh A LOT more and can cause components to wear out a lot faster.

Majorleaguebass Senior Enthusiast

Majorleaguebass

Posted
Posted
Correcto....35's and staying 35's go with a 4.56. 35's then to 37's eventually, or straight to 37's go with 4.88's. Also if you have the G80, well you do....get that out of there too. I'd swap in a TrueTrac!

 

 

4.56's are what to tall for 35's...

if i were to run that i would have to have a 37's or 38's

J-man67 Senior Enthusiast

J-man67

Posted
Posted
I have 3.73's in my truck...if you want to run 35's good, you need 4:10, if you are going to go to 37's...go with a 4:56, anything bigger than that.....its gonna run like shit, and drive like shit!!!!! Thats what my suspension guy told me and he has been doing this for a long time. if you want to go with 4:88...then you need 40's. Thats the only way that it will not drive like shit.

 

Everyone I talk to says 4.56's with 35's and 4.88's with 37's are ideal. I would go with 5.13's with 40's, but maybe thats just me.

J-man67 Senior Enthusiast

J-man67

Posted
Posted
Correcto....35's and staying 35's go with a 4.56. 35's then to 37's eventually, or straight to 37's go with 4.88's. Also if you have the G80, well you do....get that out of there too. I'd swap in a TrueTrac!

 

 

4.56's are what to tall for 35's...

if i were to run that i would have to have a 37's or 38's

 

 

I don't think they are at all. I have seen TONS of guys run that combo and their RPM's are fine all around.

2000DV4.8 Senior Enthusiast

2000DV4.8

Posted
Posted
Correcto....35's and staying 35's go with a 4.56. 35's then to 37's eventually, or straight to 37's go with 4.88's. Also if you have the G80, well you do....get that out of there too. I'd swap in a TrueTrac!

 

 

4.56's are what to tall for 35's...

if i were to run that i would have to have a 37's or 38's

 

 

I don't think they are at all. I have seen TONS of guys run that combo and their RPM's are fine all around.

 

 

 

Same here. My buddy ran 4.88s and 35s for about 3 years and loved it (it is a similar final drive ratio to stock tires with 4.10s).

 

3.73s and stock tires is a very similar final drive ratio to:

4.10s with 33s

4.56s with 35s.

4.88s with 37s.

2000DV4.8 Senior Enthusiast

2000DV4.8

Posted
Posted

Here's a gear/tire size calculator:

http://www.4lo.com/calc/gearratio.htm#ratios

 

And I did a few:

 

Stock (245/75R16)

post-35072-1222808497_thumb.jpg

 

35s and 4.10s

post-35072-1222808490_thumb.jpg

 

35s and 4.56s

post-35072-1222808483_thumb.jpg

 

EDIT: With the extra weight of the 35s, a slightly lower gear will help get the big tires moving easier, and will put less strain on the transmission.

 

EDIT2: This is where you're at right now, with 35s and 3.73s, so the 4.10s aren't that big of a difference, and might not be very noticeable on takeoff.

post-35072-1222808822_thumb.jpg

post-35072-1222808483_thumb.jpg

post-35072-1222808490_thumb.jpg

post-35072-1222808497_thumb.jpg

post-35072-1222808822_thumb.jpg

post-35072-1222808483_thumb.jpg

post-35072-1222808490_thumb.jpg

post-35072-1222808497_thumb.jpg

post-35072-1222808822_thumb.jpg

post-35072-1222808483_thumb.jpg

post-35072-1222808490_thumb.jpg

post-35072-1222808497_thumb.jpg

post-35072-1222808822_thumb.jpg

Jackson76 Enthusiast

Jackson76

Posted
  • Author
Posted

Hi guys!!! Thanks for all your post

 

Before i lift the truck i was running Toyo MT 295/70/R17 (33 x 11.50) and the truck felt great at take off and on

highway but the Toyo is a very hard tire, i mean it perfom awesome on the road and off road (traction, grip, etc) but

very hard on the suspension this tire weights 73lbs and now that im running on Toyo 35x12.50R17 the truck feel slow on take off

but not to slow on highway but a lot more hard on the suspension this tire weights 83lbs so if i go straight to BFG 37x12.50R17 this

tire weights only 72lbs compared to the 93lbs of the Toyo 37 so its lighter than the Toyos 33 and it's also a softer tire and better for the steering also.

 

On the other hand i seen that a lot of the pre-runner trucks use 4.56 gears with 37's.

 

So i guess that a 4.10 on a 35 would work fine and 4.56 for 37

 

Does anyone recommend a specific brand? i was thinking on Precision Gear

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