3.21. vs 3.92 gear

[Firebird]

After having a couple of loaners with 3.21 gears, I refuse to own one.

 

[Ramit392]

Just under 5000 miles with combo driving 60 % highway 40% Local very happy with 3.92 gear.

 

[Willwork4truck]

Lots of threads on this already, read some.

A majority of responses will likely favor the 3.92 even if not towing. A probable minority are like me and would have taken either one but the lot truck I found had 3.21’s and I’m pleased with 24 mpg at 65 mph average on a 250 mile highway only trip with only 1200 total miles on the non e torque hemi.

Do you like fast starts? 3.92. Do you live in the mountains? 3.92. Do you live where there are lots of trailer towers (even if you don’t) and are thinking about resale? 3.92.

Are you a relaxed urban grocery getter type who only occasionally dirties the bed? 3.21
Do you like getting the best overall mpg just cause’? 3.21.

What does your dealer have on the lot that you can get a good price on?

I personally think its a very smart expenditure of $95 to get the 3.92 when you order one, but I didn't go that route.

 

[HeliPilot]

My 3.21 tows my 24ft Crownline Boat without issue.

 

[Hassman]

I got the 3.21. I pull a 6k trailer up and down hills in Canada about ten weekends a summer. While towing, sometimes I wish I had the 3.92. But then when I’m empty (like 90% of the time) I love getting 20mpg on the highway (with AT tires).

You’ll be fine with a 4K trailer and 3.21. Use the gear limiter and set it to 7 on flatland and 6 on hills.

 

[Willwork4truck]

I got the 3.21. I pull a 6k trailer up and down hills in Canada about ten weekends a summer. While towing, sometimes I wish I had the 3.92. But then when I’m empty (like 90% of the time) I love getting 20mpg on the highway (with AT tires).

You’ll be fine with a 4K trailer and 3.21. Use the gear limiter and set it to 7 on flatland and 6 on hills.

I think its quite doable to tow under 5K, especially a boat (low frontal drag) with 3.21. The OP said he was NOT going to tow so except for resale considerations, towing isn’t the point (unless you are saying “I’ve got more than enough power to tow my xxx with my 3.21’s so go ahead”.

Me thinks it boils down to how “spirited” he likes to drive, if the best mpg is important and/or if he finds a great deal on one or the other lot truck.

I don’t think he can go wrong with either choice given his parameters... for others here 3.21’s are a non-starter and you have your (good) reasons why.

I’d have happily bought either one as a “non-tower”. I believe he should pick his trim, color in and out then look for absolute “must have” options, if he has any. Near the bottom of the list for a non-tower, non-racer is gears. Not anti-slip though, I think thats important.

 

[Gman]

Do you live in the mountains? 3.92.

Unless you tow in the mountains, 3.21 is fine. I have no issues exceeding the speed limit and rapidly overtaking other drivers on climbs in the mountains.

I'm also a 'spirited' driver. I dust folks off the line regularly with the 3.21. My biggest issue is that it's so easy to speed even at low RPM.

If smoking burnouts are your thing, the tires will cost more than the $95 3.92 option.

 

[Willwork4truck]

I test drove a 3.92 limited about a month before I bought. The test course had a 90 degree right turn at a busy intersection with me being on a slight uphill. I don’t know if the truck had anti-slip or not. The light turned green for the other side so I pressed down exactly the same as I always do with my Ford Edge 3.5 awd.
I left an embarrassing peel and got dirty looks from the salesman and a “oh really, did you like that” comment from my wife. I protested my innocence to no avail. I blame the 3.92’s for my loss of grandpa driver status.

 

[2wd]

The 3.21 is pretty underrated for towing (Check out post #165 for details). No one's arguing that 3.21's are better for towing, but you could argue that it's better for unloaded or light loads than the 3.92. It depends on what you prioritize.

3.92 wins at burnouts, excels if you are hooked to a trailer >50% of the time, or are the rare owner with the available Payload to tow more than 9K lbs

3.21 wins at reducing your unloaded operating costs (fuel) and wear and tear on the engine (lower RPM's @ highway,).

Some will say it's a truck, MPG be damned, but 2-3 MPG difference over 50-70K highway miles adds up.

 

[ExcursionDiesel]

The 3.21 is pretty underrated for towing (Check out post #165 for details). No one's arguing that 3.21's are better for towing, but you could argue that it's better for unloaded or light loads than the 3.92. It depends on what you prioritize.

3.92 wins at burnouts, excels if you are hooked to a trailer >50% of the time, or are the rare owner with the available Payload to tow more than 9K lbs

3.21 wins at reducing your unloaded operating costs (fuel) and wear and tear on the engine (lower RPM's @ highway,).

Some will say it's a truck, MPG be damned, but 2-3 MPG difference over 50-70K highway miles adds up.

View attachment 26770

Excellent post. No way will my 3.92 Limited 4WD ORG achieve 21 mpg average at 60mph on a long trip without a tailwind or flat ground. You are proof that these trucks can have good mpg when properly equipped with the right driving style.

 

[Willwork4truck]

Sheesh, his 59 mpg even beats my old Prius!

 

[rceagle1a]

if you are leaving it stock height id get the 3.21s

I have 3.21's and I only plan a 2- 2.5 leveling kit and 33 inch tires. I may get a 29ft lite travel trailer next year. How will my 8 speed 3.21 ratio bighorn handle it? It has the factory brake controller system.

 

[Willwork4truck]

I have 3.21's and I only plan a 2- 2.5 leveling kit and 33 inch tires. I may get a 29ft lite travel trailer next year. How will my 8 speed 3.21 ratio bighorn handle it? It has the factory brake controller system.

Hard for anyone to exactly say other than someone with an identical rear gearing and appx same wet weight trailer. Some poster a way back on the 3.21 vs 3.92 said his 7000-7500 pound trailer towed ok with 3.21’s, the bigger issue is your payload. You will run out of payload (for tongue weight and stuff) long before the hemi will run out of power to pull. Figure 13% of your fully loaded weight, to include passengers and gear. You have to weigh your rig on some scales, axle by axle, to make sure you havent overloaded one or both. A good well set up WD hitch is mandatory, as well as keeping the nose of the trailer light.

 

[Willwork4truck]

I will be adding air lift bags into the springs shortly to add 2100lbs of load capability to the rear, tires soon too as I HATE the 20 inch GARBAGE rings ram loves so much. Did I say I feel 20 inch tires are a TOTAL JOKE, yep I did,lol.

If you haven't already done so, please refer to the thread entitled
First camping trip: Success
in the general comments section. It will show you how another member towed with a big trailer close to yours, and what his comments were. I will respect the forum by not repeating his findings or adding anything else except for this one caveat: please be careful of the total (especially rear) axle weights on your truck.

 

[riccnick]

I will be adding air lift bags into the springs shortly to add 2100lbs of load capability to the rear, tires soon too as I HATE the 20 inch GARBAGE rings ram loves so much. Did I say I feel 20 inch tires are a TOTAL JOKE, yep I did,lol.

You won't be adding ANY payload capability to your truck. In reality, you'll actually DECREASE your payload by the exact weight of the added airbag system, including the airbags, lines, fittings, tanks, brackets, compressor(s), and controller. Your truck is rated for what's on the drivers door load sticker, and that's it.

 

[Willwork4truck]

That's a fact. Coming from the TT world, as well as having truck campers for years, I will say that many owners falsely believe that suspension "enhancements" increase their payload.
Nope.
Nothing short of axle swaps or moving up a series or two (2500/3500) does that. All the air bags, Timbrens, sway bars do is level out, reduce body roll and bottoming out issues. TT dealers have for years taken advantage of uninformed buyers by telling them that their 1/2T - 1500 truck could tow/carry anything... The payload sticker is the thing to go by.
Now if you are serious about staying "legal" and not breaking down your suspension then don't exceed say 80% of your payload from the trailer tongue weight and your things in the bed. That gives you a bit of a leftover capacity for the driver, fuel and passengers.
Can modern trucks carry/tow in excess of their stated sticker weights? Yep. Heck the Tundra pulled the space shuttle a few years ago...
Is it safe to do so, on a routine basis? Nope. Are you endangering yourself/passengers and others on the road if you do so? Yep.
Do many people doing this seem to really care? Nope

If you want to be "edumancated" some, look up the rv.net forums and read a bazillion threads about the issue. You will see posts about everything from 1990 Ford Rangers towing 8,000# to people advocating F450's DRW's for lawnmower trailers...

If you live in the flatlands and tow for a short distance at safe speeds (not highway posted maximums), adjust your tires accordingly, and have a well set up WD hitch then you'll probably be fine with a Rebel, or any 1500 series RAM for that matter. RAM isn't known for payload capacity, that's been the knock against them ever since the coil springs came out. If you want the max payload for a half-ton, get an F150 that has the "Max Payload" package. It's about 2700 pounds on their crew cabs, some variants (reg cab) go up to 3,000# but that's very uncommon.

 

[silver billet]

Can modern trucks carry/tow in excess of their stated sticker weights? Yep. Heck the Tundra pulled the space shuttle a few years ago...

I agree with your post, except for that statement there. That toybox didn't "pull" the space shuttle. Yes it tugged it, but it didn't do on the interstate going up a hill with 3 occupants etc etc. Pulling something in first gear for 5 inches is not the same as "rated to pull x pounds". And we also have no idea what damage occurred to the transmission while that toyota was playing marketing stunts.

So to answer your question, no, modern trucks cannot carry/tow in excess of their stated sticker weight. That rating is a rating for a reason, and blowing past it is asking for trouble sooner rather than later.

There are no magic tricks of physics here; If the truck could seriously tow/carry more, they would rate it higher, it's that simple.

And if airbags were the answer, then those RAM's with air suspension would be rated to tow/carry more, but they aren't.

 

[Blueraptor]

I got the 3.92 gears and I have drove a loaner with the 3.21 and think I actually prefer the way the 3.21 feels in every day use. My truck wants to be in the highest gear possible all the time. When you take off from a stop it wants to shift into 2nd gear as soon as the wheels start to move. If I do a quick stop and go the truck will never downshift out of 3rd gear and it feels sluggish when you try to take off in 3rd gear. It is in 6th gear at 35mph fairly often, I don't know if this is normal operation. Coming from a truck with the 2.7l Ecoboost v6, 6 speed with 3.73 gears it just feels slow in comparison. The truck I drove as a loaner felt more normal, it didn't seem to want to upshift nearly as fast. It was a fairly basic big horn with 20" wheels instead of the 22" ones I have so I imagine there is a significant weight difference but I find it hard to imagine it would make up for the difference I felt driving them around town.

 

[Willwork4truck]

I agree with your post, except for that statement there. That toybox didn't "pull" the space shuttle. Yes it tugged it, but it didn't do on the interstate going up a hill with 3 occupants etc etc. Pulling something in first gear for 5 inches is not the same as "rated to pull x pounds". And we also have no idea what damage occurred to the transmission while that toyota was playing marketing stunts.

So to answer your question, no, modern trucks cannot carry/tow in excess of their stated sticker weight. That rating is a rating for a reason, and blowing past it is asking for trouble sooner rather than later.

There are no magic tricks of physics here; If the truck could seriously tow/carry more, they would rate it higher, it's that simple.

And if airbags were the answer, then those RAM's with air suspension would be rated to tow/carry more, but they aren't.

True the toy didn't "tow" it, it "pulled" it. kinda' semantics but the point is modern engines and transmission/gears can do way more than brakes and axles can take...

 

[Gman]

If you've ever seen the performance spec's for those tugs that move giant jets around at the airport, moving something really large with a vehicle as a marketing stunt isn't a big deal.