The best rear axle ratio for me

[A4Owner]

So I will probably never tow more than about 5,000 pounds and the two main highways I take to my cottage have speed limits of 80 Km/H meaning you set it at 90 and 100Km/H meaning you set it at 119. Which rear end would you say is best for me?

 

[GKIII]

If you tow at all I'd recommend the 3.92.

 

[bigdodge]

So I will probably never tow more than about 5,000 pounds and the two main highways I take to my cottage have speed limits of 80 Km/H meaning you set it at 90 and 100Km/H meaning you set it at 119. Which rear end would you say is best for me?

did you see the thread https://5thgenrams.com/community/th...uide-to-3-21-vs-3-92-axle-ratio.16986/page-88


lots of different opinions you have to do what you feel will work for you

me I like the quick launch and tow about as much as you so the 3.92 was important to me. one reason i went through three orders.

 

[Threesuns1]

What engine are you thinking about?

 

[User_3336]

3.92. its only a $95 option. Better to get it up front.

 

[river rat]

To complete the forum trinity, might as well ask what oil to run and which tire size is best.

 

[User_3336]

Another reason I got the 3.92 was to eliminate the constant gear hunting that a 3.21 axle ratio makes truck do.

My truck pretty much stays in 8th gear all the time. I have a couple of slopes and slight inclines on my everyday commute. In a 3.21, it would be a continual 6-7-8 gear thing. I've even had a harsh downshift from 8th to 5th having to floor it a bit to keep up speed going up the same hills.

3.92 will have a higher RPM at highway speeds, lets say 70mph, about 2,000 RPM.

 

[User_3336]

To complete the forum trinity, might as well ask what oil to run and which tire size is best.

Lets NOT!

 

[A4Owner]

What engine are you thinking about?

5.7 liter

 

[Aseras]

Just check your payload on the build tool. A lot of these trucks are stupid heavy when optioned out. If you tow a LOT and carry a lot of gear you will go over payload unless you get a stripper tradesman build.

 

[Idahoktm]

Another reason I got the 3.92 was to eliminate the constant gear hunting that a 3.21 axle ratio makes truck do.

My truck pretty much stays in 8th gear all the time. I have a couple of slopes and slight inclines on my everyday commute. In a 3.21, it would be a continual 6-7-8 gear thing. I've even had a harsh downshift from 8th to 5th having to floor it a bit to keep up speed going up the same hills.

3.92 will have a higher RPM at highway speeds, lets say 70mph, about 2,000 RPM.

I took note last week...3.92 gearing: 70 mph=1700 rpm. 75 mph=1900 rpm. That's with 33" tires.

 

[deeve]

Just check your payload on the build tool. A lot of these trucks are stupid heavy when optioned out. If you tow a LOT and carry a lot of gear you will go over payload unless you get a stripper tradesman build.

Not trying to be a wise guy but what would you consider stupid heavy with low payload? Like what is considered low?

 

[A4Owner]

By the way to all 5.7s have active fuel saver MDS or do you have to order that as an option when specify the V8? And what is MDS?

 

[Idahoktm]

By the way to all 5.7s have active fuel saver MDS or do you have to order that as an option when specify the V8? And what is MDS?

All 5.7's have MDS.

What Is Hemi MDS?

We explain how Chrysler Hemi MDS cylinder deactivation works, what goes wrong, and how to fix it when it breaks.

www.motortrend.com

 

[User_3336]

All 5.7's have MDS.

What Is Hemi MDS?

We explain how Chrysler Hemi MDS cylinder deactivation works, what goes wrong, and how to fix it when it breaks.

www.motortrend.com

I turn that stupid crap off every time I get in my truck. My "-" button is pressed everytime I get on the highway.

 

[bigdodge]

I turn that stupid crap off every time I get in my truck. My "-" button is pressed everytime I get on the highway.

and after reading that article I am going to have to teach the wife how to use the "-" button.

 

[Mountain Whiskey]

Truck=3.92

Girly Grocery Getter= 3.21

You can decide what is best for you.

 

[A4Owner]

Truck=3.92

Girly Grocery Getter= 3.21

You can decide what is best for you.

Hahaha...because a black 1500 is so girly lol. Anyways I figure a 3:21 with MDS on mid grade fuel shouldn't be that bad on the highway. Should it?

 

[GKIII]

Hahaha...because a black 1500 is so girly lol. Anyways I figure a 3:21 with MDS on mid grade fuel shouldn't be that bad on the highway. Should it?

My suggestion when you're buying a $50k+ V8 truck is not to worry about MPGs and get something that suits your needs the best. So to reiterate what I said above, if you tow at all you'll be much happier with the 3.92.

MDS is usually never on unless you are going below 60 mph without a trailer anyway.

 

[mikeru82]

All 5.7's have MDS.

What Is Hemi MDS?

We explain how Chrysler Hemi MDS cylinder deactivation works, what goes wrong, and how to fix it when it breaks.

www.motortrend.com

Thanks for including that article. It explains why I didn't see any noticeable difference in fuel economy when I tested out MDS on and MDS off on my last truck. And makes me feel better about keeping it off on my current truck.

MDS is usually never on unless you are going below 60 mph without a trailer anyway.

Which describes how I use my truck more than 90% of the time