Axle ratio swap, AMERICAN AXLE, do they have taller gears than 3:73?

[BBowers]

I have a 05 3500 drw auto 4x4. I currently have 3:73's and am thankful I don't have 4. 10s! I am thinkin it might be more economical to switch to like 3. 54's or taller if possible than buying a gv over/underdrive. I don't really have $2600 bucks laying around for the marginal decrease in revs it affords in top gear. I would love to turn about 1600 rpm at 70 mph maybe even 1400-1500. Any ideas?

 

[NDanecker]

I have a 05 3500 drw auto 4x4. I currently have 3:73's and am thankful I don't have 4. 10s! I am thinkin it might be more economical to switch to like 3. 54's or taller if possible than buying a gv over/underdrive. I don't really have $2600 bucks laying around for the marginal decrease in revs it affords in top gear. I would love to turn about 1600 rpm at 70 mph maybe even 1400-1500. Any ideas?

I just recently swapped out the stock 3. 73 for 4. 10 and she runs MUCH better. I run 315's though. Around town mileage suffered with the taller tires and low gears but help on the highway. My average was about 17 mpg. Highway I could easily break 20 but around town I got around 13-14. With the new geers I lost around 1 - 2 mpg on the highway but around town went up. My towing mileage also went up from 11 to about 15-16..... huge difference! So, it really depends on how you use the truck.



Watch out as lowering gear ratio will also decrease torque that the pavement see's which will require more on the go pedal to maintain speed on hills, stop and go traffice, towing, etc so the savings may not be there. Not to mention the extra stress on the drivetrain.



Cost me about $2200 to complete the swapp at a local performance shop (Xtreme Diesel) which did a (((EDIT: THEY DID A **** POOR JOB!!! I SPOKE WAY TOO FREAKIN SOON WHEN I SAID THEY DID A GOOD JOB. WHEN I DROVE AWAY I CALLED PHIL OF XTREME DIESEL AND QUESTIONED BY THE GEARS ARE SINGING. PHIL STATED ‘THE GEARS NEED TO BREAK IN AND THE WHINE WILL GO AWAY AFTER A FEW THOUSAND MILES’ SO I DROVE IT A FEW THOUSAND MILES. THE TRUCK HAD NO GEAR WHINE BEFORE BUT SINGS LIKE A FREAKIN CANARY RIGHT NOW AFTER THEY DID THE GEAR SWAP. THEIR SUGGESTION TO ‘WAIT TILL THE GEARS BREAK IN’ IS BS AND JUST A POOR JOB TO GET RID OF ME. WENT BACK THERE, THEY ALLEGALDY RE-SHIMMED THE GEARS AND SAID NOTHING WAS WRONG. REAR END ACTUALLY SINGS WORSE NOW AFTER THE RE-SHIMMING!!! ***!!!!! AND I HAD TO FIGHT WITH THEM AS THEY WANTED ME TO PAY THE 5 HOURS SHOP TIME ($495) TO INSPECT AND RE-SHIM THE REAR EVEN THOUGH THE TRUCK IS WORSE NOW!!! YOU HAVE NO FREAKING IDEA HOW ****** I AM!!! I’VE DONE MANY AXLE SWAPS FROM FORD 8. 8” TO GM 10 BOLTS AND MOST RECENTLY MY FORD 9” IN MY S-10 SMALL BLOCK TRUCK. I HAD THEM DO THE GEAR SWAP BECAUSE I CURRENTLY MOVED AND HAVE NO GARAGE TILL MY BROTHER BUILDS/FINISHES HIS SHOP. XTREME DIESEL DOES NOT KNOW HOW TO DO GEAR SWAPS…STAY THE F**** AWAY FROM THEM. JMO…. YOU’LL FIND OUT THE HARD IF YOU DON’T HEED THIS WARNING!!!))) I went with OEM AAM gears in the rear but {don't remember the name} up front as they were hard to get.

 

[ilovetrains]

I have been hoping they will release some taller gears. Someone in another post had contacted AAM direct. They said DC was working with them to put out another ratio, higher, like 314 or something.

 

[Trent]

Please post said thread

 

[jwduke]

3. 14's wouldn't be worth a darn to pull a camper or anything with really. Would make your truck more of a pleasure vehicle.

 

[MarcRoth]

Taller... You guys mean a shortter gear not TALLER Taller is such as 4:10 4:56 short is a 3:14 marc

 

[6 2 Carl]

Taller... You guys mean a shortter gear not TALLER Taller is such as 4:10 4:56 short is a 3:14 marc

It's the other way around. Gear ratio's are weird that way. A "lower or shorter" gear is numerically higher, and a "taller or higher" gear is numerically lower.



Carl

 

[bpenrod]

..... for the marginal decrease in revs it affords in top gear. I would love to turn about 1600 rpm at 70 mph maybe even 1400-1500. Any ideas?

The GV unit with 3. 73's puts you right where you want to be, 1600 rpm at 70 mph with the stock tires. I cruise to work everyday at around 78 mph and around 1800 rpm and really enjoy having less engine noise. The splitting is also nice with a heavy load. One dis-advantage would be not using it in 4x4. I went the GV route and have been really happy with it. Plus I like being able to switch my truck back to stock very easily. I had a new driveshaft made and kept the old output casing off the transfer case. I can bolt those back in and be back to stock in a few short hours if I go to sell it or trade it in.

 

[Cummins Cowboy]

on the other thread they said some 3:42's which would be just right with the G56, seems to me the easier thing to do would be to change the overdrive in the g56, that way there is only 2 axle choices to worry about, now if they do the 3:42's we will be at 3, I sure hope they do something at the midyear change, because I want taller gears than 3:73

 

[DHerbeck]

Hey bpenrod-



My truck is coming with 3. 73's. I am very interested in the GV OD unit. Is 1600 PRM at 70MPH underpowered? I can't believe it would take more than 200 HP and 300 lb. ft. of torque to make an empty truck roll at highway speed. If you slow down to say 60 or 65, is the RPM too low? Lugging? Buzzing in the cab? Am I correct that this is about a $2700. 00 unit? And of course, when you want to tow, turn it off, which I presume would put you back to 1:1? Is that right? How much does this help your highway mileage? That is the only reason I would do it. I too thought about taller gears, but that is so permanent, as in you can't switch it in and out like you can the GV. Any other driving impression would be appreciated.



Dave

 

[MRFost]

MEthinks that the stock tires and stock gears are fine -- just need seventh gear! They left one out. If I could get a higher OD, that would be good, but don't want TOO large a jump from 5th. I'm thinking maybe instead of 0. 79:1, OD should be like 0. 69 or the like.

 

[steved]

MEthinks that the stock tires and stock gears are fine -- just need seventh gear! They left one out. If I could get a higher OD, that would be good, but don't want TOO large a jump from 5th. I'm thinking maybe instead of 0. 79:1, OD should be like 0. 69 or the like.

I'm always going for seventh... it just isn't there!



They either need another gear, or the previously mention 3. 42 for the "car"-trucks that some of us own... I got a set of 3. 73s sitting here right now if anyone is interested in a set for the 9. 25 and 10. 5... I'm keeping my 4. 10s as I can't see where changing gears will make any difference in overall mileage, just the speed/rpm you get your best mileage... and I'm OK going 60mph!! (please don't run me over in your Honda... )



steved

 

[ilovetrains]

JGann is the guy had some email contact with AAM. 3. 42 seems about right. 7th gear, and maybe 8th, would be awful nice though.

 

[steved]

JGann is the guy had some email contact with AAM. 3. 42 seems about right. 7th gear, and maybe 8th, would be awful nice though.

I think I would rather have the (transmission) gears... then you could simply choose to run one lower if needed... and still have all your low gear grunt.



Of course, if they add another gear we might as well buy a CXT!



steved

 

[John Prince]

I have 3. 54's with 285's in my 97, My new 06 is a 3. 73 6 spd. With my 97 if I am pulling a heavy load say 22,000 lbs first cout be a little lower and rev could be a lot lower. The 6 speed could have 3. 54's and be lower than my 97. I will go to 285's and see what happens one day. I have not pulled my dozer yet with the 06. I can bet the new truck will do a better job.

Running empty it would be nice to be at 2000 for 70mph bet 2300rpm is not that far off. I was looking at a Gear Vender till I found out a Jake Brake was a NO, NO. It would have been nice to split gears and had a 6th + an over when empty.

John

 

[6 2 Carl]

3. 14's wouldn't be worth a darn to pull a camper or anything with really. Would make your truck more of a pleasure vehicle.

Actually 3. 14' or 3. 08 wouldn't be that bad with a G56, you would just have to tow in 5th gear. The NV5600 in 6th gear make the effective gear ratio 2. 99 (4. 1*0. 73= 2. 99). So a G56 in 5th gear and 3. 14's will be same or even slightly better then an Nv5600 in 6th with 4. 10's.

 

[klenger]

Actually 3. 14' or 3. 08 wouldn't be that bad with a G56, you would just have to tow in 5th gear. The NV5600 in 6th gear make the effective gear ratio 2. 99 (4. 1*0. 73= 2. 99). So a G56 in 5th gear and 3. 14's will be same or even slightly better then an Nv5600 in 6th with 4. 10's.

I agree. It would be like having 4. 10's for towing and 3. 55 for empty. Who needs 6 gears for towing anyway. Just consider 6th gear a real overdrive.

 

[TowPro]

I was just checking out American Axle & Manufacturings website and noticed all the rears they make come with rations at least as low as 3:54, some are way down into the 2's and go as high as 6:33.

 

[Trent]

I still want some better gearing with this G56 but it doesn't look like it will happen. Here is the response I got from Mike at ringpinion.com on AAM 11. 5 gearing.



Good Morning Trent and happy New Year!



My purchasing department has explored a few different avenues and

neither AAM, nor any other aftermarket supplier is planning on cutting

any ratio's higher than 3. 73's ("higher" meaning numerically lower). I

wish I had better news for ya. Take care and let me know if there is

anything else I can help you with.

 

[betterthanstock]

I would love to turn about 1600 rpm at 70 mph maybe even 1400-1500. Any ideas?

Play with tires (285, 315) before gears.



I've done both. I went from stock tires to 315, then from 4. 10 to 3. 73.

I think it's almost perfect now. (1925 rpm @70 with an NV5600 6 speed).

I shift into overdrive (6th speed) at about 50 mph. Anything taller and I would need to constantly shift up/down at 55-60 mph. The auto has an even taller overdrive, so if taller gears were available you would get constant up/down shifting at about 60-70 with every little hill or headwind.



A GV has the disadvantage of another set of gears (typically 3% loss thru any gear) so the fuel mileage is not what it would be if you could have an even taller single overdrive, NOT a double overdrive (stock and GV).



If I had your transmission I would put 285 or 33" tires on.