It does not.
Honestly, If I put on 285/65R20 in place of the 285/60R20 I doubt anyone would even notice anyway.
The Custom Suspension clause is separate and distinct. They are not related.
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Gearing and tires
- Thread starter BigBlack
- Start date
It does not.
Honestly, If I put on 285/65R20 in place of the 285/60R20 I doubt anyone would even notice anyway.
The Custom Suspension clause is separate and distinct. They are not related.
Has anyone actually swapped the gears on their 2019 2500? If so did you have any issues and can you tell me what gears you used? Trying to get it done myself but there's some hold up with not knowing what to use that I'm trying to find an answer.
UglyViking
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I know this is pretty old but I'm looking at the numbers on that chart you shared and the surprising thing is that there isn't as big a difference between the stock 3.73 gears for 33" stock vs 37s. If you look how they have the gearing setup from the factory it's clearly balanced for MPG over power, and the 3.73s don't leave much room to step up or down to stay in that band.
Obviously this is all standard stuff, you raise your tire size you're going to lose acceleration, higher gearing you're going to gain acceleration and lose MPG. It's all a balance. I'm just mostly surprised that the difference between the stock tires and 37s is only a jump of 267 RPM at 1:1 gearing, which is 4th on the 68rfe, so those two overdrive gears should push so that you're not seeing much loss in MPG I'd imagine.
So, what is the thought on 35s with 3.73s? I have a 2019 Bighorn 6.4. I'm planning on upgrading tires here pretty quick. Came to me with 275/70r18, looking to go to 35x12.5. I don't do a whole lot of towing, but I do get off road quite a bit. And then theres the snow...thanks for any input.
UglyViking
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Look at post #12 there is a pdf you can look at, I'd say you should be fine with 35s for your case.
Thanks. I looked at the table, I assume the table numbers are RPM? I just started to second guess everything...one forum says one tging, another, something different. I was really wondering how much of a difference there was.
UglyViking
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The table is RPM at 65mph in 1:1 gearing. If you have a CTD with the 68rfe it has 2 overdrive gears so these numbers should be lower. I'm unsure where this chart came from so while that is generally the case I'm not 100% sure in this case. Seems to match up with my experience though.
As with everything on any vehicle there are a ton of guys who are willing to tell you exactly what to do, most are based on opinions and nothing more. I would say, generally speaking, your case should be ok but two things to note 1. it will be slower to accelerate, 2. it will put more strain on your transmission. Is it enough to rapidly accelerate the wear on the trans so you're halving it's life? Probably not. 20%? Maybe but who knows, it could go just as long as with factory size tires. Personally, I'd set aside a little cash if you plan to run 35s or larger. Run it without the gear change for a bit and see how you like it. If it feels like a dog then get online and start digging into what others have done, pros/cons of different sizes, etc. There is no "correct answer" here, just a range of more and less correct ones.
Here's two good resources to determine your final gear ratios/RPM's/tire size, etc.
The first is a modified version of a gear calculator I found years ago when I first bought my 04.5. You can play with it to see the RPM difference in each gear with different tire sizes.
This online resource was posted by a member on one of the boards, perhaps it was here, I just don't recall.
www.blocklayer.com
These just give you an idea of the shift points, RPM, etc. Knowing where your power band is is still necessary. The final factor is seat time.
The first is a modified version of a gear calculator I found years ago when I first bought my 04.5. You can play with it to see the RPM difference in each gear with different tire sizes.
This online resource was posted by a member on one of the boards, perhaps it was here, I just don't recall.
Gearing Analyzer with Shift Tracer
Enter gear ratios, tire and diff ratio to analyze RPM vs velocity at shift points with tracer
www.blocklayer.com
These just give you an idea of the shift points, RPM, etc. Knowing where your power band is is still necessary. The final factor is seat time.
Catmechanic
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I've looked a LOT with no luck so I'm revising an older thread to see if anyone has actually located a source for gears for the 2019+ HD's? I'm not at all new to regearing a vehicle, I just for the life of me cannot find anything but factory ratios available. Looking for 4.30 or 4.56-ish for my 2020 2500 CTD
I have a 2019 2500 and am looking for the same information. I can find up to 2018 but not 2019 and newer. I am installing 37"s and would like to swap gears. Was thinking 4.10s but maybe I should be thinking 4.30s.
Squatch
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Did you look it up by your axle type? AAM 11.5 or whatever it is?
H3LZSN1P3R
You're doing it wrong
I remember when we used to run 37s on our 2nd gen 12 valve with 3.55 gears and still had power to pull a 13k trailer.... that was with a whopping 140hp at the crank... these trucks pull so effortlessly with 33s i cant imagine 35/37s change that enough to dump 3 grand in gearing lol
Catmechanic
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I wouldn't be dumping $3k into gearing. I'd be dumping $1k or so for parts. Between doing it for work and having a side gig in the off-road world, I've set up hundreds of gearsets.
H3LZSN1P3R
You're doing it wrong
Here just the parts are over 1500 and i would do it myself aswell but most people would not do it themselfs