Just wondering how much real world difference there really is between these two ratios. I've seen some pretty quick 1/4 mile times on this forum with 3.55's and in respect to towing if both vehicles are in 4th at 70 mph towing your looking at about 250 rpm difference between the 3.55's and the 3.92's. Based on this I'm thinking if you find a deal you like don't let this spec sway you too much either way, what do y'all think? Oh and Merry Christmas everybody!
3.55 vs 3.92
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·Any change up in gear ratio will definitely multiply your torque. Going from a 3.55 to a 3.92 is not a huge increase but you'll feel it. Besides the RPM difference, the truck will feel a bit more powerful as you have increased the low end torque with the change.
For some reason, every '11 Express I saw in person or on paper in another dealer's inventory while shopping regional dealers had 3:55 and no LSD. Every '12 had 3:55 and with LSD. Go figure. Maybe Dodge is pushing dealers to take the LSD on the '12's.
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I was more concerned about getting LSD that I didn't pay attention to the ratio until I saw my build sheet. Thought all LSD's at one point were 3.92, but found out after I bought my truck it was 3.55 LSD. :doh:
Ya with 35" tires that would suck. I would go to 4.56s with that size tire.
I had a 04 with the factory 17" wheels( 29.5" tall tires)and at that point the 3.55s was the only option. (no lsd) When you went for the 20" wheels (33" tall tire) they put the 3.92s with the lsd.
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I think if you are not going to tow and just use the truck as a cruiser then either gear set will do. If you do want to tow, or run at the track then why not get the lowest gear set? More important, get the L/S diff.
I had to do a inventory search on the dodge web site to find the combination I wanted and it was some 80 miles away (may not sound like much but I'm in los angeles with many dealers around).
One thing I couldn't figure out about the Rams is how they package their vehicles. Ford and Chevy have option packages that include lower gears and L/S which would make sense for a truck if you are going to tow or haul. But Ram, lower gears with limited slip are hard to find in this area. The only thing I can think of is maybe they have a supply issue with the limited slip units????
I had to do a inventory search on the dodge web site to find the combination I wanted and it was some 80 miles away (may not sound like much but I'm in los angeles with many dealers around).
One thing I couldn't figure out about the Rams is how they package their vehicles. Ford and Chevy have option packages that include lower gears and L/S which would make sense for a truck if you are going to tow or haul. But Ram, lower gears with limited slip are hard to find in this area. The only thing I can think of is maybe they have a supply issue with the limited slip units????
Same here. 3.92 w/ LSD 4x4 QC was make or break for my purchase decision. They had to bring a vehicle in from over 100 miles away. Every truck in local inventories were 3.55's. If I could not have gotten a the truck I wanted I probably would have been looking at a 3/4 T Chevy with the 6.2L engine w/ 4.10 gear
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Gonna have to agree with this one....very tough to find a LSD in my neck of the woods too. Chevy has a great little package called the All-Star package that was a decent value for just this market. They even discounted (supposedly) by packaging things people wanted most. The Z71 off road package was also ideal with the A/T tires, skid plates...etc. Too bad I couldn't get pass their recycled design from 1997. Dodge styling inside and out won me over.:smileup:
I don't know...I'm not sure the difference between 3:55 and 3:92 is that big a deal "generally"....and notice I said generally. With the 6-speed trans in my 2wd '12 Express regular cab/short bed, I can select a proper rpm to suit my "empty" driving and my towing needs. I think these transmissions function quite well when you pay attention to trans temp and pay attention to not lugging the motor. I lived for about 300,000 miles with a GM 700-R4 and 3:42 gears for towing and off roading in 4WD mode by paying attention to the aforementioned issues, and this was not a very robust tranny. Keeping rpm at an optimum point by going between 3rd(regular driver) and 4th(overdrive), the tranny and engine worked less and lived longer. Higher rpm isn't always a bad thing up to a point.
I would agree that when you start upping the ante with even bigger tires and towing loads approaching the max for the given truck, the lower gears are better. Hotrodding a lower rear gear is also a pleasant benefit for optimum performance. My travel trailer is a hair over 5000 pounds fully loaded and ready-to-go, and my truck with 3:55 has no issue at all pulling it. Worst case scenarios usually only require going to 4th for a brief period which is about 2600 rpm. Otherwise the truck is usually loafing along. I can also see the benefit of the 3:92 when you're towing "and" you have a fully loaded 4-dr, 4wd, with all the extras and lots of people and lots of gear. Maybe there is no perfect gear, because there is no perfect, consistent situation. Things change.
I would agree that when you start upping the ante with even bigger tires and towing loads approaching the max for the given truck, the lower gears are better. Hotrodding a lower rear gear is also a pleasant benefit for optimum performance. My travel trailer is a hair over 5000 pounds fully loaded and ready-to-go, and my truck with 3:55 has no issue at all pulling it. Worst case scenarios usually only require going to 4th for a brief period which is about 2600 rpm. Otherwise the truck is usually loafing along. I can also see the benefit of the 3:92 when you're towing "and" you have a fully loaded 4-dr, 4wd, with all the extras and lots of people and lots of gear. Maybe there is no perfect gear, because there is no perfect, consistent situation. Things change.
The problem with the Chevy is they only come with 3.42 gears unless you get the max tow package. That package gets you the 6.2L engine and 3.73 gears.
Before I bought my 2012 with 3.92's, I test drove one with 3.55 gears. Personally, I thought it was a dog. There's no reason a truck should run 50+ mph before shifting out of 1st gear!! That's exactly what it did with 3.55's and 20" wheels. Guys should also consider the not-so-perfect gearing of the Ram. 1st gear is fairly tall. The jump from 3rd to 4th gear is large. 6th gear is tall...it turns 2,000 rpm's at nearly 75 mph. I would never consider anything taller than 3.92's. And Dodge offers 3.21 gears!:Wow1:
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Mine was factory ordered with 3.92's after reading up on them in this forum. Most trucks on lots here are 3.55's. (Its also a rare Laramie with the 40/20/40 seat - no gigantic console on the floor)
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Most every truck on the lots here had 3.55 gears. Not really a big deal to me. I never tow, and if I do it will only be something like a Uhaul trailer to move or to help a friend out. It's my daily driver in the winter and for rainy summer days.
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