AAM Ring & Pinion

[Drewhenry]

I have had little luck--none finding optional gearsets for my rearend. I am aware of the need for other ratios. Can anyone tell me who would manufacture a custom set for me? I figure 3. 07 would save lots of fuel and I will still have plenty of power. Any info would be greatly appreciated.

Thanks!

Andy

 

[AKaiser]

Based on guys putting 35 inch tires on their trucks saying they lose MPG, I doubt you'll see a positive figure by going to 3. 07s. I figure with my G56, going to 3. 42s would make sense, but I don't think even the G56 would support 3. 07s and still show a positive MPG trend.

 

[Panther1400]

35 inch tires with an auto lose mpg, 35 with g56 still good mpg. My observation.

 

[Tinman]

Bigger tires lose milage b/o the extra rotating weight. Lighter tires with taller gearing might to well if you don't tow. I'd be easier to get an over/over drive gear from an after market vendor such as US Gear.

 

[MickeyMiller]

I don't think I lost any milage with the 35" tires on my 3. 73 NV5600 combo. Besides, you only need gears if you don't have enough engine! With the Cummins... who needs gears?

 

[AKaiser]

35 inch tires with an auto lose mpg, 35 with g56 still good mpg. My observation.

Sounds right.

 

[p-Bar]

Think about around town driving, seems to me it would suck for fuel mileage.

 

[Drewhenry]

optional ratios

All ya'lls answers are interesting but similar to polititians you completely skirted the issue and did not answer my question--except for Tynmann. I have considered an OD unit-that will not wear out unlike tires @$300. 00 each that may only give 50K miles.

 

[TowPro]

I think you have a Dana 80HB in 2003? What about the 3:55's that you could buy in 1998? They might fit.

 

[JFaulkner]

I think that the cost of a custom set of gears would cost so much that the added fuel milage would never make up the cost. I would also like taller gears, maybe not 3. 07 but I think 3. 36 would be good. I think that with the final drive of my G56 combined 3. 36's would be similar to the 3. 55's that were available in the 2nd gen's with the nv5600. And for anyone that says that taller gears wouldn't work for towing seem to forget that with a manual transmission I can tow in whatever gear I want. If I can tow in 6th now at say 2500rpm, with the taller gears I would just use 5th for towing (at slower speeds) and use 6th for empty milage.



I wouldn't rule out 3. 07's, I'm up for anything as long as the jump is large enough to actually notice. (3. 73 to 3. 55 would be worthless)

 

[Drewhenry]

I chose 3. 07 in order to approximate 55mph rpm @70 mph. It seems to me that sometime back there was a similar discussion but I cannot locate it @ this time. A cnc programmer was going to make a set of gears and a lengthy discussion followed and ultimately somebody suggested a certain mfg that would build custom gears. I have had no luck in finding that post. My truck is an early 04 and has the AAM 11. 5 not the Dana 80HB. 3. 31 would be great also as to allow 70mph in the sweet spot but as JFaulkner stated " I can tow in any gear I want. " With 3. 07 tow in 5th--no problem.

 

[AKaiser]

I would think you would want to keep your 55 MPH lowest cruising speed within the lower limits of the torque band in top gear. I can do that on 3. 42s with a G56, but you would need 3. 55s to do that on the NV5600. I think that would put 65 and 75 well within the acceptable fuel consumption area of the engine in top gear. I know it will with 33" tires. Just my thoughts. I did the figures on the klenger.net xls file.

 

[AKaiser]

I think that the cost of a custom set of gears would cost so much that the added fuel milage would never make up the cost. I would also like taller gears, maybe not 3. 07 but I think 3. 36 would be good. I think that with the final drive of my G56 combined 3. 36's would be similar to the 3. 55's that were available in the 2nd gen's with the nv5600. And for anyone that says that taller gears wouldn't work for towing seem to forget that with a manual transmission I can tow in whatever gear I want. If I can tow in 6th now at say 2500rpm, with the taller gears I would just use 5th for towing (at slower speeds) and use 6th for empty milage.



I wouldn't rule out 3. 07's, I'm up for anything as long as the jump is large enough to actually notice. (3. 73 to 3. 55 would be worthless)

That's assuming that the smaller ring and pinion of the faster gears will be up to the task.

 

[JFaulkner]

That's assuming that the smaller ring and pinion of the faster gears will be up to the task.

I doubt that would be an issue with a daily driver. Sledpulling or dragracing maybe. Strength could be easily compensated with better material. (depleted uranium maybe:-laf )

 

[AKaiser]

I doubt that would be an issue with a daily driver. Sledpulling or dragracing maybe. Strength could be easily compensated with better material. (depleted uranium maybe:-laf )

Truly, but I doubt you want to go down the DU road. You thought brake dust was bad :-laf