Advantage to re-gearing axles?

[Sticks]

Rather than hijack any of the other threads -

I see a bunch of people wanting the 4:10 in a SRW but that is not an option, even on a custom order. You have to go DRW to get it from the factory.

Would there be an advantage to re-gearing the front (4wd) and rear axles to get the gear ratio that Ram won't give us, barring voiding the axle warranty?

 

[Hoefler]

Voids the whole drive train warranty as well as the emission warranty. All the certifications are based off how the vehicle left the factory, any changes at all will put it out of specs for the certification.

 

[Sticks]

Huh.

I can almost see the drivetrain warranty, at a stretch, but emissions?

 

[SnoKing]

Voids the whole drive train warranty as well as the emission warranty. All the certifications are based off how the vehicle left the factory, any changes at all will put it out of specs for the certification.

So you think the SRW and Duallies under go separate certifications? SNOKING

 

[jhenderson]

The only warrenty voided woul be the differentials, they are the only affected part. The problem is it's not cost effective if you can't do it yourself.

 

[Deleted member 995608]

Changing the r&p is not going to void any warranties other than the specific differential itself.

 

[mwilson]

If the dealer does it the rears should be covered for one year under the parts replacement warranty. The base vehicle warranty on the rears would be voided.

This is one area where big trucks differ. If a customer desires a different ratio when the vehicle is new a carrier exchange is in play. We order chucks in the ratio requested by the customer and swap them out. All warranty remains in effect. The take outs are returned to the axle manufacturers for use in the reman carrier programs. The only charge involved is the freight both ways and the swap labor. Many times that is factored into the sales deal.

Of course theses ratios are all available to order, where in the Ram that is not the case.

Mike.

 

[SnoKing]

I wonder when Cummins12V98 had Dave Smith willing to change the gears ratio in his current truck what they told him about warranty? SNOKING

 

[TCDiesel]

If you ever did R&P changes Front and Rear ,its a PITR , All R&Ps are married You must change them both, mwilson comment, the entire diff is 1 assembly, unlike AAMs in the Ram. I think its a big mistake that Ram does not allow gear options, I can only speculate why they don't. One guess is most owners have no idea what gearing is, most salesman are clueless, its like this most owner never wash the engine compartments BC its NOT stated in the owners manual, Some buyers would not buy a truck BC it stated in the owners manual to wash the engine compartment ,their competitors would use it as a selling point .......I know this sounds stupid but we charge to clean some engine compartments, BC they are so filthy. then the owner complains that its not stated in the manual so they should not have to pay, that's the mentality in North America today.

 

[SnoKing]

I think RAM's logic is that 3.42 gears in the SRW trucks will handle the GCWR and max trailer weight that they spec for the truck, therefore no other ratios are needed. With wide spaced 6 speed auto trannies and wide torque curves the truck operates to their specs! Also wanting to tow a heavier load with the required lower gears helps move people to the duallies better suited to the heavier loads! SNOKING

 

[Joseph Donnelly]

I agree with Snoking on this. The 3.42s maximize mpg and lessen engine wear over the life of the truck. They aren't so far from the 3.55s of the second gen Rams, and the Aisin in particular has a steeper first gear than the old automatics.

 

[SnoKing]

Deeper vs steeper!!!! SNOKING

 

[Cummins12V98]

I wonder when Cummins12V98 had Dave Smith willing to change the gears ratio in his current truck what they told him about warranty? SNOKING

They did say it would void the differentials warranty only but the re gear would have 12mo 12k warranty.

 

[Mawvelous]

What's the advantage?
Lower torque multiplication get heavy loads moving easier from standing start.
Pertaining to above less strain involved.
If you just gotta have a step ladder to get into it because of a lift and 37 inch tall tires
You just gotta smoke that Ford or Chevy stoplight to stoplight

The 3.42 gears put the engine it it's power range on the highway in 5th especially. 6th gear cruising more economical. Many complain about lack og low speed grunt. Very few complaints towing at highway speeds. Most of the recent comparison reviews bear this out. Ram loses drag races with the other 2 but is in every race up the Davis Dam or Eisenhower grade pulls.
I like the way this pulls my trailer as compared to 2005 with 4 speed auto & 3:73 gearing. I had to put an overdrivev lockout on that truck because it would hunt in & out on long pulls. I would have it locked out mode running 2100 + rpm. This truck I ofeten don't bother with locking out 6th it shifts back as needed. Even with 6th locked out there is a lot less NVH due to running about 200 RPM lower and still maintaining power.

 

[TJJEEPER]

My guess is the 4.10 is only available in the 3500 because it has a different spec for emissions. Only a guess.

I'm towing about 14,000 with my 3,73 signature truck and if I was going to pull any more I'd want the 4.10.

 

[grabinov]

I'm still curious if anyone has tried this (swapping ratios). You'd have to find some way to tell the computer that the truck was using a different axle ratios or all kinds of things would be confused (besides just the odometer). Somewhere in the"base" settings for the truck the manufacturer must tell the computer which ration is installed. If the computers are the same in all the trucks there must be a way to swap ratios in the computer, at least if you stick to factory ring and pinion combinations.

My personal interest is twofold: I'd like to add bigger tires and I'd like a lower gear for starting off on a hill with my trailer which, alas, is a situation I'm stuck with at my house. Since I rarely drive (the truck) over 75, I have plenty of gear at the big end...

 

[rscurtis]

No need to worry about the speedometer, as the signal is picked up at the OD of the ring gear. It doesn't matter what the ratios are prior to that point. 3.42's would be perfect for my signature truck, but it's not worth the trouble, even considering the fuel savings.

 

[SBeretz]

My Dad has a 2012 with the G56 and went from 3.73 to 3.42's. He did have the dealer do it and they probably charged a little more than I would have wanted to pay, but my Dad keeps his trucks for a long time. He is really enjoying the little extra fuel mileage and less noise. I wished I would have done the 3.42's about 8 years ago.

 

[grabinov]

AEV, which is working on upgrades to the Ram similar to those they do for Jeeps, says they are going to offer a "ProCal Calibration Module" (a programmer) with their suspension kits to allow the user to make adjustments to the computer for tire size and final drive ratio.

Interestingly on a related note, they have figured out the Chrysler computer sufficiently well (for Jeeps at least) to change the computer settings so that the Tire pressure monitoring system will not constantly alarm when Jeeps deflate their tires for use off road. Maybe we can rid ourselves of the constraints of the "80 PSI only" TPMS on the 2500s! It would be nice to be able to cut rear tire pressures to 65 when running around unloaded without setting off dashboard alarms!

 

[NDanecker]

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