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4.30 gears?

62K views 135 replies 33 participants last post by  Devilman 
#1 ·
Does anybody still make 4.30 gears? Or anything between 4.10 and 4.56? I'm on 37's and for what I do I think the 4.30 would be perfect.
 
#3 ·
Do you know what you are running for rpm at 70 and 75mph?
 
#7 ·
I think you can do it with EFI live, I'm waiting for EZlynk to be released and I'm sure it won't be too long before it can change tire sizes. Also, you can send a private message to 4x4x4 and he has a tool that does it that he rents out
 
#8 ·
i didnt think that a gear change would affect the speedometer as the speed sensor is on the carrier and not on the transmission output shaft? Please correct me if I am mistaken.
 
#9 ·
Not sure about the newer ones but I had the dealer calibrate my speedo after upsizing my tires what they changed was the "pinion factor". I think the gearing would change things.

I guess the take away is the dealer can flash the truck for proper speedo readings.

Like I said mine is a 12 and I have no idea if the newer ones are different.


Ramit 2012 CCSB ST G56 3:42 Mineral Gray MOPAR
 
#11 ·
I am fixing to do a gear change in mine. Going to put 4.44 gears in mine. Wanted 4.56 but there is no factory gears available right now in 4.56 for rear. I am running 37s on 2" lift. If you have a2014 or newer Ram 2500, you have to use the 2011-2013 ring and pinion set up and make sure the bearing kit has the conversion bearing.
 
#12 ·
Y'all must be pulling some heavy loads to need those low gears. I have a 2015 DRW 3500 with 3.42 gears, with 24" Alcoa's with 325/45/24 tires. Tires are almost 36" tall. I've pulled a 28' enclosed with a 4500 lb CTS-V Cadillac with spare tires, jacks & tools. The trailer has a generator also. I've pulled open trailers with decent size tractor also. I don't have any issues running 80-90 mph with any of those loads behind the truck. At 80 mph the tach is at 1600 rpm. I've had 04, 05 and 12 models with 3.73 gears. The truck I have now with the 3.42 gears pulls better stock than the 12 did tuned. I'm sure if I started getting into larger trailers with multiple vehicles, I would definitely have to run lower gears.
 
#16 ·
I did the 4.56 swap as well and do love it. Will not be messing with tuning etc while warranties are still in place. It is a good boost for those who aren't willing to run their tunes. Especially when majority of us have oversizes wheels or tires.

Lower gear (4.56): more stress on all components behind the diff (axles, etc.)

Higher gear (3.42): more stress on the tranny & clutch
 
#13 ·
There's no doubt that the truck will pull it. I did it for 70k. In that time I also went through a trans and then a TC shortly after. The truck is doggy and it's hard on everything trying to tow that heavy with such a tall gear ratio. I ended up going with 4.10's and are getting put in right now. Really looking to getting a load behind it when I get it back. I also only tow around 10k
 
#15 ·
Be careful running stock gears and 37" tires, at least that's what I was told did some of the damage to my trans. I am now running 4.44's and a new trans from Revmax. The guys at Revmax said a combination of factory gears and switching power levels is what did me in. I know Suncoast and Revmax require proof of gear change to honor warranty if you have taller tires.
 
#20 ·
Can I get your opinions? I'm getting ready to buy some gears and can't decide on 4.11 or 4.30. I'm running 37" tires and tow about 5-7k most of the time and 10k on rare occasions. I was thinking the 4.11 since I drive 70 miles a day on the freeway with very little traffic and that would keep at least a little bit of the mileage that I'm getting now.

Thanks for the input.
 
#21 ·
If I was to do it again I would do 4.30. The 4.10s are alot better for sure but think the 30s would be the sweet spot. I'm on 37's and almost always have nearly 2000lb in the box plus in the summer I'll be towing nearly 10k on top of it. I think the 4.10s are going to leave me in a weird spot in the rpm range for towing and it might be doing some gear hunting.

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#22 ·
I would go with 4:30 or 4:44. Truck is way under geared from the start. If you use 3.73 gears is gear ratio calculator and 37's you come out with like 4.18, so you always step up one. When going to big tires you want to go up a little to help strain on transmission because of weight. Now 4:11 would put you back close to the factory gear ratio of 3:42 and 33's. Because the 68 transmission is not the greatest, i am giving up a little on fuel to run 4.44 gears. Once I get it tuned I will gain it back. The reason I am going with 4.44 gear ratio is because it is factory gears
 
#26 ·
Do you have any suggestions on where to get the 4.44 gears? Are they AAM?
 
#27 ·
WOW, I didn't realize mileage would drop so far. Could be driving habits and you might do more city driving then me but I'm around 20mpg with 37" before and after tuning.

You can get factory 4.44 gears cheaper than aftermarket gears. Almost buy complete set of OEM gears for same price as just rear aftermarket. West Coast Differentials is the cheapest on bearing kits.
That might be the case but since I don't tow really heavy and from the post above it looks as if I'm going to lose a bit of MPGs I'm thinking a little more for 4.30 or maybe the 4.10 now lol. My daily drive is 70 miles on the freeway early morning and afternoon when the traffic is light.
 
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#30 ·
Ron's Machining services. $565.00 for front and rear ring and pinion in 4.44 gear ratio. Ordered the 2014 to 2016 for the front 9.25 and 2013 for the 11.5. Going to order bearing kits from West Coast Differentials. 354.02 for rear (comes with conversion bearings) and 171.93 for front. 525.95 plus shipping. Gears ordered. Bearings will be next week.
 
#32 ·
I ended up going with 4.10's as 4:30's were backordered at that time, but, in retrospect I wish I had waited. The 4.10's are good, in fact they are GREAT on the highway, but as a all around choice for 37's there is no doubt the 4:30 would be the better choice.
If there was a way I could substitute without having to incur the expense again it would already be done.
 
#34 ·
I guess it depends on how much highway driving you do, how fast you drive on the highway and how much you pull. I drive 70-80 and mostly empty highway, so the 4.10 is good and I don't pull much but I feel the 4.30 would keep it in the power band more at lower speeds/ headwinds and certainly better when pulling. If I was pulling more often and drove 65-70 and not long distance interstate running I would certainly consider 4.44. I feel a little more gear is better than less if your going to pull much with 37's.
For me 4.30 would have been perfect. The 4.10's are perfect when I long distance travel but as soon as I hook onto something I'm instantly wishing for the 30's. It's not that I'm short on power- but I know it could have been better.
 
#35 ·
so 4.30 4.44 or 4.56 for 37s?

You definitely want more gear than you need since the tire is not only taller, but it is also heavier.
 
#36 ·
You can get any gear ratio for these trucks but you have to convert the rear back to an 11.5 set up instead of 11.8. Just differentials has the parts to do it and I ran 4.56 gears with 37 and 38.5 tires. I run 4.10 with 35 inch tires. They make 4.30 gears in the 11.8 and I think they may have 4.56 gears now also. The only difference is the pinion shaft and the front bearing.
 
#37 ·
What is going to be the cheaper switch then. Finding a gear that doesn't need to convert ? Which gears do you not have to convert ?


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#38 ·
You can get the conversion bearing kit that comes with all the bearings you need. I went with 4.44 gear ratio because it is factory OEM gears. Around 354 with shipping for rear bearings kit. If you scroll up you will see my post with prices. They don't make a rear ring and pinion over 4.10 gear for the 14 up 2500. You have to use 2013 gear set with conversion bearings
 
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