I don't want to use 3rd gear!

[FordRanger1991]

Hey guys i just had a question about some lower gearing. I have some headers with a 2.5" exhaust that leads to a flowmaster and i have an electric fan. So i feel that the engine is putting out a little more power than stock. I put a 4 inch lift on my 91 ranger that has a 2.9 liter engine a 5 speed as well as 33 inch tires. As of now i have stock 3.73 gears. That is fine for around town driving but when i hit the freeway going up 6% grades becomes a little challenge. I have to use 3rd gear on freeway and i don't want to use it anymore. I am tired of cars passing me on the hills because i wont pin my truck at 4500 rpm to keep the 70 mph. So i am wondering if 4.56 gears would do the trick for me to enable me to keep it in 4th gear going up those steep hills. If anyone has some knowledge about this that would be great! Also, personal experience would be appreciated.
Thanks a lot for your time!

 

[4x4junkie]

I'd get some 4.88 gears for that.
I have 5.13s w/35s on my 2.9L truck (right about the same overall) and it's just about perfect for it. 6% grades no problem with a downshift to 4th.

 

[Sasquatch_Ryda]

4500 rpm ain't gonna hurt a damn thing on that engine either.

 

[FordRanger1991]

Haha ya I know it wont hurt it getting the rpm up that high because I tested the engine a couple times while loosing some toyotas up those hills
but thanks for the comments!

 

[kryptonitecb]

There is a calculator I found online that had all the parameters you would need to find out what gearing you wanted.

http://www.grimmjeeper.com/gears.html

This one is much better than any of the ones the tech library has AND!!! it already has the transmission gearing programed in. All you do is play with your tire size/gear ratio combination until you find the one you like.

Have fun

 

[FordRanger1991]

Ya that calculator was sweet it tells you your speeds at different rpms for every gear. So thanks for that because it was really helpfull.
I also learned that if I am in first gear I can go 70 mph if I rev at 1200 rpm Haha
Thanks again!

 

[dla]

from 3.73 to:

• 4.10 is a 10% change
• 4.30 is a 15% change
• 4.56 is a 22% change

 

[kryptonitecb]

One thing I found out today is that the gear ratio's may not be correct. I have a m50d with 4.10's and 37" tires. The calculator told me I'd be off by about 10mph at 60. Hopped in my truck with a buddies gps and found out that my speedo is now dead on So its not as perfect of a calculator as I had been thinking it was.

 

[FordRanger1991]

Ok ya I understand. For me when I looked it seemed to be pretty close because I put in my gears (3.73 what i have now) and it said my rpm at different speeds and it seemed to be right on target with what really happens. So it seems close at least for my set up.