6.4 Hemi Gear Swap

[WY.Ram]

With the 5.13 they are aam?
How does your truck get down the highway st say 70-75 mph
Any info on this gear set and how your truck operates would be awesome
Like fuel mileage
Rpm at certain speeds etc
The shop i found to do it was right at 3k for everything
Gear ratio didn't seem to effect the price
Thank you for any info
I'm hoping to fo this soon and doing all the research i can
I'm thinking 5.13 that 6.4 is a beast
I also have 35 tires

And @theviking

Huge post but I know how long and far I searched for info before and if this helps, awesome.

AAM Part number for the 5.13 gear set, 9.25 front differential is #40136007 and rear 11.5 is #40030646 (pic shown)

2016 Ram 2500, 6.4 L, 6 Speed, 66k mi
35" (34.5") Mickey Thompson MTs worn to 33.75". I run 91 octane with a Hemifever tune and longtube headers.

Take my gas milage with a grain, I post for informational purposes only, I love to make my truck jump and go. All a Ford has to do is wiggle near me and I am on it. Many trucks see Power Wagon on my tailgate and they come flying after me, I show em full throttle in any gear and they stay back and don't even try, no shizzle.

I did the regear for 37" tires, I'm enjoying the experience with 35s so much I haven't bothered with the 37s yet.

Traffic flys out here, 85mph in a posted work zone will keep you alive but not unharassed in the left. My truck handles the crazy high speed no problems.

I drive elevations from 6,700ft to 10,000ft regularly and above 10,000 ft as often as I can.

If I could take my foot out of it who knows what kind of mpg I could get but so far no luck there.

I don't tow , but she's usually loaded down with gear. With a Full tank she came in at 7,640 lbs on a certified scale.

I read the following rpm from a digital readout.

5:13 diff gear set:
MPG 10.1 / 12.5 (EVIC, WOT and 80 to 90 mph)

Trans 4th gear
60 miles an hour 2950 RPM
65 miles an hour 3330 RPM
70 miles an hour 3550 RPM
75 miles an hour 3815 RPM

Trans 5th gear
55 miles an hour 2280 RPM
60 miles an hour 2450 RPM
65 miles an hour 2680 RPM
70 miles an hour 2890 RPM
75 miles an hour 3100 RPM
80 miles an hour 3300 RPM

Trans 6th gear
65 miles an hour 2082 RPM
70 miles an hour 2200 RPM
75 miles an hour 2400 RPM
80 miles an hour 2550 RPM


4:10 Diff Gear:
MPG 10.5 / 12.8 (EVIC, WOT and 80 to 90 mph)

Trans 5th gear
70 miles an hour 2345 RPM
75 miles an hour 2475 RPM
80 miles an hour 2650 RPM
85 miles an hour 2785 RPM

Trans 6th gear
75 miles perhour 1880 RPM
80 miles an hour 2010 RPM
85 miles perhour 2094 RPM

Any other info I can help with, let me know.


2016 RAM 2500 pw | 392ci w 6spd | CAI w ARH long tubes & Solo | Diablo T2 w HF tune | 5.13 AAM w 35" Mickey MTs | Custom Graphics w illegal tint | Dodge Off-Road

 

[NewBlackDak]

Any other info I can help with, let me know.

Do you think 5.13 on stock wheels and tires would be crazy?


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[SETEX 6.4]

Do you think 5.13 on stock wheels and tires would be crazy?


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Crazy good for towing and in the Hill country! If it was to low of gearing to your liking, you could always throw some 35's on the factory wheels when you need new tires. Even with no lift they will fit with only slight rubbing on the control arms at full lock.

2014 Ram 2500 Mega Cab 6.4 Hemi 4:10 Gears Ram Boxes 35x12.50R18 on Factory Wheels
Sent from my SAMSUNG-SM-G891A using Tapatalk

 

[RAM_Designs]

FWIW, I have 4.88's with 37" tires and I would not want to go to 5.13's...but I'm at a lower altitude, don't tow, and I drive 70-80mph every day.

 

[WY.Ram]

Do you think 5.13 on stock wheels and tires would be crazy?


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Assuming your stock tire is a 33"? It would really depend on how you use your truck, you would definitely be on the lower end of a regear. Like SETEX 6.4 said crazy good for towing and Hill country and if you do feel you went to too low you can change to a larger tire. The tire being a consumable, the size is an excellent way to fine tune the truck's output.

Having the tire size option helped me finally make the decision and then to sleep at night while the mod was being implemented. It was a difficult trigger to pull, I get it. The axle shop wasn't going to put my 4.10s back in if I didn't like my 5.13s, at least not for free. Lol

I'm not sure what truck you have but the Thuren Fabrication website (click the link "tech" at the top) has excellent info on how big a tire these trucks can run with stock and suspension lifts.







2016 RAM 2500 pw | 392ci w 6spd | CAI w ARH long tubes & Solo | Diablo T2 w HF tune | 5.13 AAM w 35" Mickey MTs | Custom Graphics w illegal tint | Dodge Off-Road

 

[allenmp]

And @theviking

Huge post but I know how long and far I searched for info before and if this helps, awesome.

AAM Part number for the 5.13 gear set, 9.25 front differential is #40136007 and rear 11.5 is #40030646 (pic shown)

2016 Ram 2500, 6.4 L, 6 Speed, 66k mi
35" (34.5") Mickey Thompson MTs worn to 33.75". I run 91 octane with a Hemifever tune and longtube headers.

Take my gas milage with a grain, I post for informational purposes only, I love to make my truck jump and go. All a Ford has to do is wiggle near me and I am on it. Many trucks see Power Wagon on my tailgate and they come flying after me, I show em full throttle in any gear and they stay back and don't even try, no shizzle.

I did the regear for 37" tires, I'm enjoying the experience with 35s so much I haven't bothered with the 37s yet.

Traffic flys out here, 85mph in a posted work zone will keep you alive but not unharassed in the left. My truck handles the crazy high speed no problems.

I drive elevations from 6,700ft to 10,000ft regularly and above 10,000 ft as often as I can.

If I could take my foot out of it who knows what kind of mpg I could get but so far no luck there.

I don't tow , but she's usually loaded down with gear. With a Full tank she came in at 7,640 lbs on a certified scale.

I read the following rpm from a digital readout.

5:13 diff gear set:
MPG 10.1 / 12.5 (EVIC, WOT and 80 to 90 mph)

Trans 4th gear
60 miles an hour 2950 RPM
65 miles an hour 3330 RPM
70 miles an hour 3550 RPM
75 miles an hour 3815 RPM

Trans 5th gear
55 miles an hour 2280 RPM
60 miles an hour 2450 RPM
65 miles an hour 2680 RPM
70 miles an hour 2890 RPM
75 miles an hour 3100 RPM
80 miles an hour 3300 RPM

Trans 6th gear
65 miles an hour 2082 RPM
70 miles an hour 2200 RPM
75 miles an hour 2400 RPM
80 miles an hour 2550 RPM


4:10 Diff Gear:
MPG 10.5 / 12.8 (EVIC, WOT and 80 to 90 mph)

Trans 5th gear
70 miles an hour 2345 RPM
75 miles an hour 2475 RPM
80 miles an hour 2650 RPM
85 miles an hour 2785 RPM

Trans 6th gear
75 miles perhour 1880 RPM
80 miles an hour 2010 RPM
85 miles perhour 2094 RPM

Any other info I can help with, let me know.


2016 RAM 2500 pw | 392ci w 6spd | CAI w ARH long tubes & Solo | Diablo T2 w HF tune | 5.13 AAM w 35" Mickey MTs | Custom Graphics w illegal tint | Dodge Off-Road

Wow i would have thought you would be more than 2200 @ 70 in 6th
That is an excellent review on your running conditions
Thank you
I would have thought 5.13 with 35' would've been just screaming going down the highway
I was reluctant to go with 4.88 but now I'm thinking 4.88 or even the 5.13 would be awesome
I don't pull very often either but do almost all highway driving
With the 3.73 it's always lugging so i drive it in manual in 5th most of the time
Are your gears noisy at all
Just wondering i have heard some are noisier than others
I agree with you i do like to punch it on occasion myself lol
But usually by the time my 3.73 get going and the trans has to drop 2 gears to get rpm up they are looking gone Haha
I did run em with a tundra awhile back
Both took off from about 65 he got about 3/4 off a truck on me before i started reeling him back in lol
But we backed off before we got to fast
Great info thanks again

 

[jaflowers]

Could someone please explain why this part couldn't be used in a 2014+ 2500 please. It's the same size rear, 11.5", and also the same 14 bolt and the same 9x41. Thanks to any help explaining this to a mechanical noobe.

AAM 40005988 Chrysler Ram 3500 2003 - 2013 11.5" 14 Bolt - Rear Axle 4.56 / 9x41

Seems like that would match up to the ones the make for the front.

AAM 40146853 Chrysler Ram 2500 / 3500 2014 - 2018 9.25" Beam - Front Axle 4.56 / 9x41

 

[NewBlackDak]

Crazy good for towing and in the Hill country! If it was to low of gearing to your liking, you could always throw some 35's on the factory wheels when you need new tires. Even with no lift they will fit with only slight rubbing on the control arms at full lock.

2014 Ram 2500 Mega Cab 6.4 Hemi 4:10 Gears Ram Boxes 35x12.50R18 on Factory Wheels
Sent from my SAMSUNG-SM-G891A using Tapatalk

Assuming your stock tire is a 33"? It would really depend on how you use your truck, you would definitely be on the lower end of a regear. Like SETEX 6.4 said crazy good for towing and Hill country and if you do feel you went to too low you can change to a larger tire. The tire being a consumable, the size is an excellent way to fine tune the truck's output.

Having the tire size option helped me finally make the decision and then to sleep at night while the mod was being implemented. It was a difficult trigger to pull, I get it. The axle shop wasn't going to put my 4.10s back in if I didn't like my 5.13s, at least not for free. Lol

I'm not sure what truck you have but the Thuren Fabrication website (click the link "tech" at the top) has excellent info on how big a tire these trucks can run with stock and suspension lifts.







2016 RAM 2500 pw | 392ci w 6spd | CAI w ARH long tubes & Solo | Diablo T2 w HF tune | 5.13 AAM w 35" Mickey MTs | Custom Graphics w illegal tint | Dodge Off-Road

Mine is a ‘14 MC Laramie 6.4 4x4 4.10 stock except for tailgate assist and fab fours rear bumper(wife + fence post = bad).
I live in Utah, and have to tow over a pass in every direction. 37K of my 74K miles have been towing. I have a little daily driver now, so the truck has a trailer hitched and/or a load in the bed almost any time it’s driven.


There won’t be any lift going on. I’m not about it, and everybody already complains about climbing up into it. I can’t deal with any rubbing either. It takes every bit of steering it can muster to work my 33’ travel trailer into some of the spots around here. I’ll go check out Thuren’s site to find the max size, and work out the RPM numbers.


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[WY.Ram]

Wow i would have thought you would be more than 2200 @ 70 in 6th
That is an excellent review on your running conditions
Thank you
I would have thought 5.13 with 35' would've been just screaming going down the highway
I was reluctant to go with 4.88 but now I'm thinking 4.88 or even the 5.13 would be awesome
I don't pull very often either but do almost all highway driving
With the 3.73 it's always lugging so i drive it in manual in 5th most of the time
Are your gears noisy at all
Just wondering i have heard some are noisier than others
I agree with you i do like to punch it on occasion myself lol
But usually by the time my 3.73 get going and the trans has to drop 2 gears to get rpm up they are looking gone Haha
I did run em with a tundra awhile back
Both took off from about 65 he got about 3/4 off a truck on me before i started pumping him back in lol
But we backed off before we got to fast
Great info thanks again

I totally agree with the preconceived, I thought a 5.13 ratio would have the truck screaming at highway & interstate speeds but it's not nearly low as my mind had the ratio before I was driving it. I mean I've never had a vehicle geared lower then 4.10 / 4.11 ish so when 5.13 was an option it kinda freaked me out. "um no thanks, I need to go faster than 30mph."
But I was mistaken. It's more so a testament to how flipn steep FCA geared the 66RFE. I don't need my truck to go 140mph (at least not often) and then throw a limit at 105 mph.

Any way, I think you asked if I could hear them and no, not even a little. Smooth and silent.


2016 RAM 2500 pw | 392ci w 6spd | CAI w ARH long tubes & Solo | Diablo T2 w HF tune | 5.13 AAM w 35" Mickey MTs | Custom Graphics w illegal tint | Dodge Off-Road

 

[allenmp]

I totally agree with the preconceived, I thought a 5.13 ratio would have the truck screaming at highway & interstate speeds but it's not nearly low as my mind had the ratio before I was driving it. I mean I've never had a vehicle geared lower then 4.10 / 4.11 ish so when 5.13 was an option it kinda freaked me out. "um no thanks, I need to go faster than 30mph."
But I was mistaken. It's more so a testament to how flipn steep FCA geared the 66RFE. I don't need my truck to go 140mph (at least not often) and then throw a limit at 105 mph.

Any way, I think you asked if I could hear them and no, not even a little. Smooth and silent.


2016 RAM 2500 pw | 392ci w 6spd | CAI w ARH long tubes & Solo | Diablo T2 w HF tune | 5.13 AAM w 35" Mickey MTs | Custom Graphics w illegal tint | Dodge Off-Road

Thanks WY
Now I'm thinking 5.13
I am with you i don't care to ever have my tuck 100+ atleast not on regular occasion
I just want it to carry itself easier with out all the damn lugging or down shifting
I can't imagine all the shifting is good on the transmission
I grew up in the 80's when a 4.11 was a go to gear for street light to street light
You could get to 90 in a hurry but that's about if unless you wanted to break something lol
So I'm thinking with 4.88 I'm gonna be screaming at 70 mph
Then i see where your running at 70 and think wow that is perfect
As i age going 80 and 90 just don't happen but 70 is my usual cruise speed on the highway
Gave me some more to think on
Thanks

 

[WY.Ram]

Could someone please explain why this part couldn't be used in a 2014+ 2500 please. It's the same size rear, 11.5", and also the same 14 bolt and the same 9x41. Thanks to any help explaining this to a mechanical noobe.

AAM 40005988 Chrysler Ram 3500 2003 - 2013 11.5" 14 Bolt - Rear Axle 4.56 / 9x41

Seems like that would match up to the ones the make for the front.

AAM 40146853 Chrysler Ram 2500 / 3500 2014 - 2018 9.25" Beam - Front Axle 4.56 / 9x41

I thought I posted this next little tidbit but I guess forgot: I think you are right and my guess would be that it could possibly work, it's at least worth asking an experienced RAM axle shop because the only reason the 5.13 is available from AAM for the 2500 is FCA offered that ratio for one of the 3500 models. The 4th gen 3500 has an 11.8 rear diff but the ring and pinion for the 3500s 11.8 rear diff fits the 2500s 11.5 rear diff.

I know it's not your exact scenario but if the 4th gen 3500 and 2500 can use the same gear set I would guess it's not the first time FCA did this.




2016 RAM 2500 pw | 392ci w 6spd | CAI w ARH long tubes & Solo | Diablo T2 w HF tune | 5.13 AAM w 35" Mickey MTs | Custom Graphics w illegal tint | Dodge Off-Road

 

[Mountaineer83]

So I am torn between the ratio I should go with for my application. I have been leaning toward 4.88s, but am now considering 5.13s. I know several of you said 4.88s, but just wanted to give a little more info about my application.

My scenario is as follows:
-I have factory 4.10 rear
-I run 275/65/20 tires (34.1"). I wont be going larger due to bed rail to 5th wheel clearance, if anything I'll go back to the 285/60/20 (33.6")
-I live in Southern West Virginia, so we have
hilly terrain, even on our main highways and interstates
- I tow our 5th wheel maybe 5 times a year (about 14k pounds)
- I tow smaller loads under 3500lbs maybe 10 times a year
-otherwise, I use my truck for daily truck stuff

So, those of you who have regeared, would you go 4.88 (quoted Yukon gears) or go 5.13 in AAM? I want to maximize this modification and get the best balance between daily use and towing heavy.

 

[WY.Ram]

So I am torn between the ratio I should go with for my application. I have been leaning toward 4.88s, but am now considering 5.13s. I know several of you said 4.88s, but just wanted to give a little more info about my application.

My scenario is as follows:
-I have factory 4.10 rear
-I run 275/65/20 tires (34.1"). I wont be going larger due to bed rail to 5th wheel clearance, if anything I'll go back to the 285/60/20 (33.6")
-I live in Southern West Virginia, so we have
hilly terrain, even on our main highways and interstates
- I tow our 5th wheel maybe 5 times a year (about 14k pounds)
- I tow smaller loads under 3500lbs maybe 10 times a year
-otherwise, I use my truck for daily truck stuff

So, those of you who have regeared, would you go 4.88 (quoted Yukon gears) or go 5.13 in AAM? I want to maximize this modification and get the best balance between daily use and towing heavy.

On average what kind of distance & speed do You drive daily?



2016 RAM 2500 pw | 392ci w 6spd | CAI w ARH long tubes & Solo | Diablo T2 w HF tune | 5.13 AAM w 35" Mickey MTs | Custom Graphics w illegal tint | Dodge Off-Road

 

[Mountaineer83]

Generally speaking, under 70-75. Right now I drive around 100 miles a day, but that will be changing soon once I have an government issued vehicle. So, then it will be driven mostly on weekends. Shorter trips mostly to lowes, home depot, etc.

 

[WY.Ram]

I think you'll be happy with either one. 5.13 isnt too low for me, my tires are 33.75 right now and im forced to drive 80-85 (or 60) for 10 miles either direction for milk. I would cast my 2¢ for the 5:13 for the above listed, the towing, Hill Country, the Cost, not a large daily or weekly commute. The 4:88 is a great choice but if you're spinning 4:10 now and not happy with eM, then the 5:13 is Just a bit lower gear, increasing the distance between you and the 4:10 's.

I was driving a 500 mile commute every week for three Years and the majority of the distance was done 80-85 mph, not any more, but if I were still long Commuting the 85 mph (2650 rpM) is a little hot for a 3hr Cruise and I would move to my intended 37" tires very soon. 75-80 mph I'll cruise there and not even bat an eye right now, barely hear the headers at 70-75.

Probably doesn't help you whole lot but I don't think either will be a disappoint and if the entire 70K member body voted, it might be a 50_50 split, Lo L




2016 RAM 2500 pw | 392ci w 6spd | CAI w ARH long tubes & Solo | Diablo T2 w HF tune | 5.13 AAM w 35" Mickey MTs | Custom Graphics w illegal tint | Dodge Off-Road

 

[Don_T]

I have an ‘18 Ram 3500 regular cab with the 6.4 motor. I pull a 5th wheel camper that weighs 15k pounds. The truck came with 4.10 gears. I have 295/70R18 Michelin Defender tires. The gears have been changed to 5.13 ratio, AAM in the rear and Nitro in the front. At 70 MPH I run at 2200 RPM and it feels fine. The new gears make a difference towing but the truck still struggles up the steeper interstate highway hills. My mileage changed very little over all but I drive it easy.

If not for heavy towing I would be happy with the truck but I need it to pull the mountain passes and last a long time so I am going back to diesel power in the near future.


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[U&A]

5.13’s


Sent while firmly grasping my redline lubed RAM [emoji231]

 

[Mountaineer83]

I will most likely go 5.13s just for towing purposes. I love my truck and only tow a few times a year. So I can't justify a new diesel anytime soon. But one day, I will have a new dually 3500 tow rig....one day.

 

[olyelr]

I will most likely go 5.13s just for towing purposes. I love my truck and only tow a few times a year. So I can't justify a new diesel anytime soon. But one day, I will have a new dually 3500 tow rig....one day.

Ive always wanted to have an excuse to have to get a dually LOL.

 

[U&A]

Ive always wanted to have an excuse to have to get a dually LOL.

Why do you need an excuse? If you want something.... go get it!

The one thing that always confuses me is when some dude gets sports car or a musclecar he does not need everybody praise is it and loves it and does not question it as a decision.

He got the car because he wanted it and it was fun.

But then when somebody gets a truck, maybe only because they WANT it or is maybe more of a truck than they honestly need they get criticized.

What do you need that for?
Do you even tow anything?

My favorite is when guys at work think you just daily drive you truck to the grocery store because “we never see you towing or hauling anything”. ....What the ****? Am I supposed to bring my truck to work and show them every time i hook up a trailer or fill the bed with wood?

MY POINT,

get what you want and **** everyone else.




Sent while firmly grasping my redline lubed RAM [emoji231]