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Is it worth it to change ring and pinion ratios in 02 Dodge Cummins?

M
Nov 26, 2007
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13
18
I have 3.55 in it now and will mainly be towing a 27' travel trailer and 4 place enclosed trailer and occasionaly a two 3 seater pwcs. Is it worth the money to change gearing? What would a good ratio be?
 
R
Jan 14, 2009
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11
18
Chelan
I would say no, unless your truck has a 35" inch tall tire or bigger. I,ve got 4.10 in my cummins with 35" toyo mt's. The big reason trucks come with 3.55 is to get better milage. The trucks now days have so much HP/Torque they do not always need the lower gear sets. My dodge came stock with 4.10 and many times I wish I had 3.55= more MPG.
 
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big_wally81

Active member
Jan 22, 2008
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duluth minnesota
my 02 cummins also has the 3.55's in it and i like them better than the 4.10's. i guess if it always has a trailer on it i could see changing the gearing. it seems like my truck really likes to sit between 2000-2100 rpm and that is just about 70mph so it has worked out perfect for towing the race car trailer down the highway.
 
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Tec

Well-known member
Mar 31, 2008
679
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Fraser, CO
Auto or Manuel? I've got 4:10's in the dually with stock 31.5" tires, I thought about going to 3:73's or 3:55's? but I tow a 20' enclosed daily with it. I'm happy with the fuel mileage at 18 unloaded, but to get their I've got to keep it under 70! Around 2200 RPM's

The last quote i got for gear changes was like $2,200.00 :eek: for another $800 you could get a gear Vendors double overdrive! Turn your 4 speed auto into 8 speed. The final drive was like 3:20!!
 
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Tec

Well-known member
Mar 31, 2008
679
308
63
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Fraser, CO
my truck is an auto


A 27' travel trailer is going to put your stock clutches and TC through hell with 3:55's, especially if your pulling any hills! You might want to look into a TC and upgraded tranny before gears? Our trucks have 4 clutches in the stock auto, a friend of mine that builds 47RE's can get up to 6 if he can get all the shims to line up?
 
S
Nov 24, 2001
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Lewiston, ID
I dont have cummins but i do alot of building on 4x4's ( mostly toyotas) my thought are that it is always a good idea to gear for the tires. I think it is most important if you have an auto. the computer sences many things to properly do what it needs2 to.. By changing tires and not gears it will trick the comp an you may have a diff shift point that may not be desirable for the driving you do. I see alot of people buy jacket up trucks and complain of no power. come to find out gears were not changed. instant feel of power gain. not to mension your speedo will be off.
 
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