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3.21 gear ratio rant & question
#12
I have no idea why other than a fraction of fuel mileage that Dodge would do this. 20 inch wheels and 3.21 really hurts the take off and gives lower mileage in town. I drove a 3.92 and a 3.21 back to back and it was like a different world. FYI, Dodge required 4.10s with factory 20s in 02 when the 3rd gen Ram came out. I guess CAFE rules and the higher HP of the 09 hemi made them change their minds. I was really surprised at how many trucks were equiped with 3.21s when I was shopping for my 09.
#13
#14
#15
just go with the 4.56's because there's a high chance you'll regret not getting them when you get the 4.10's... with the 4.56's you cant go any higher on our axles without alot more money and work. They cost the same so as i said in your exhaust thread, go all out!
#16
Thats what im thinking, its just i would like to know what kind of power im going to have in top end and what kind of MPG ill be getting at 70-80 MPH
#17
This is exactly why gear ratio was one of the top things I looked at on this truck. Window sticker as well as the axle tag in front of right rear wheel on rear housing. On my 06 FX4 I had done gears with Yukon 4.56 and between the rebuild kit, gears and install, it cost me $2200.00. I had a custom dyno tune on the truck so I could recalibrate the speedo and had the top end limiter removed but with 4.56's and 34" tires, top end was 101 mph. ( before the regear, in drive, could easily peg the speedo in 3rd gear, then it would shift into 4th/OD at 121 with the stock 3.73's. ) My advise, I wouldn't do 4.56's again, I do too much highway driving now, unless you are going with 35"+ tires, 4.10 is enough gear here.
#19
You can go as tall as you want with respect to 4.10s or 4.56s but be sure to think about your warranty. There's only one trim level with the 4.10s from the factory so if you put anything over 3.92s on your truck, just be sure you're willing to overlook the potential warranty issues if anything goes wrong. Not trying to rain on anyone's parade but just something to consider.
Jason
Jason
#20
Help!!?
Would someone please take pity on engine-ignorant dullards like me and explain something?
What do you guys mean by "3.21" and these other similar numbers? It doesn't correspond the gear ratios since the 5-45RFE first gear is 1:3.00, right?
(BTW, the link below (from 2003) has a good description of the history and gearing from sgbofav.) :
https://dodgeforum.com/forum/dodge-r...e-5-45rfe.html
Thanks a bunch!
What do you guys mean by "3.21" and these other similar numbers? It doesn't correspond the gear ratios since the 5-45RFE first gear is 1:3.00, right?
(BTW, the link below (from 2003) has a good description of the history and gearing from sgbofav.) :
https://dodgeforum.com/forum/dodge-r...e-5-45rfe.html
Thanks a bunch!