2021 Classic Warlock differential whine in reverse(?)

[IGottaQ]

Test drove a 2021 Classic Warlock V6 4X4 today: 33,000 miles, 3.55 differential.
Carfax and inspection indicate the truck has been well-maintained.
After 15" on the road, shifted into reverse and heard a distinct whine while backing from what sounded like the differential.
Didn't sound horrible, but very noticeable. Unusual to me, but maybe that's just how the gears sound in reverse(?)
Mentioned to salesman -they didn't say much.
Is the differential whine common in reverse, or something to flag?
Thanks for your time.

 

[IGottaQ]

"bump"
Maybe I exceeded the Q limit on this forum LOL-anyway, assumed this is an EZ Q(?)
Common for a 3.55 differential to whine in reverse?
Any opinions appreciated.

 

[Redz72]

I wouldn’t say any whine in reverse is common, with the exception of a 4 cyl 5 speed manual on it way to redlining in reverse. Sounds like a red flag if I was in your shoes.

 

[IGottaQ]

Test drive on another 2021 with 3.55 gears today-
Not exact 1:1 test -this truck had the anti-spin rear diff.
Slight intermittent whine in reverse -not as loud or consistent as the other truck.
Note: whine from both trucks was at a normal/reasonable speed in reverse.

Going to get an opinion from the service mgr at whatever dealer I end up buying from (before buying LOL).

 

[IGottaQ]

I wouldn’t say any whine in reverse is common, with the exception of a 4 cyl 5 speed manual on it way to redlining in reverse. Sounds like a red flag if I was in your shoes.

Redz72, thanks for your reply-
just saw it -have thread set to "watch" -thought I'd get email updates.

 

[mikeru82]

Test drive on another 2021 with 3.55 gears today-
Not exact 1:1 test -this truck had the anti-spin rear diff.
Slight intermittent whine in reverse -not as loud or consistent as the other truck.
Note: whine from both trucks was at a normal/reasonable speed in reverse.

Going to get an opinion from the service mgr at whatever dealer I end up buying from (before buying LOL).

I have no idea if that's normal. Your Warlock is a 4th gen, and I'm not privy to the differences (if any) between 4th gen and 5th gen diffs. I don't remember either of the 4th gens I've owned whining when reversing, but then again both of those were 3.92 gears. I don't think I've driven a 4th gen or 5th gen with the 3.55 gearing.

 

[IGottaQ]

I have no idea if that's normal. Your Warlock is a 4th gen, and I'm not privy to the differences (if any) between 4th gen and 5th gen diffs. I don't remember either of the 4th gens I've owned whining when reversing, but then again both of those were 3.92 gears. I don't think I've driven a 4th gen or 5th gen with the 3.55 gearing.

Mike, thanks for your reply-
Whine in reverse was very obvious on the first truck -55 thread views and no responses from anyone familiar with that whine.
Leads me to agree w/Red at this point: red flag.
3.55 happened to be on the first truck I looked at -do very little towing so would be fine with the standard 3.21.

 

[Darksteel165]

Mike, thanks for your reply-
Whine in reverse was very obvious on the first truck -55 thread views and no responses from anyone familiar with that whine.
Leads me to agree w/Red at this point: red flag.
3.55 happened to be on the first truck I looked at -do very little towing so would be fine with the standard 3.21.

55 thread views by people who have 5th gen Rams :-/

 

[IGottaQ]

55 thread views by people who have 5th gen Rams :-/

?
Can only assume that right?
Post is in 4th Gen forum -expect 4th Gen owners do stop by here right? LOL
Surprised there weren't a few 4th Gen responses with feedback on this topic.

 

[Darksteel165]

?
Can only assume that right?
Post is in 4th Gen forum -expect 4th Gen owners do stop by here right? LOL
Surprised there weren't a few 4th Gen responses with feedback on this topic.

This website is called "5thgenrams.com"
Yes there is a 4th gen section, but this is clearly for 5th gen owners.
Sure you might get a couple here or there, about as much as the competitor section (likely even less)
There are other 4th gen forums which you would likely get much better responses from is all I am saying.

 

[mikeru82]

Meh...Not a big deal that you posted here. Not all of us are gen snobs
I'm very active in other Ram forums, with lots of 4th gen traffic. I don't remember reading many complaints about rear end whine in general. Doesn't seem like a common issue. Maybe someone ran the rear diff dry or replaced with the wrong fluid. Who knows? You may want to steer clear of that truck if you have other options.

 

[IGottaQ]

Thanks for your replies-
Realize this is "5thgenrams" -but when I googled for applicable forums your 4th gen forum appeared the most active so, here I am LOL.
If there's a better forum to post on, LMK and I'll move along!

 

[Eighty]

I have a 3.55, and I’ll admit that mine is fairly noisy in reverse. Not sure if it sounds like yours without hearing yours, though.
I’ve never driven a 3.92 or 3.21 Ram, so I don’t know if mine sounds different from those.

 

[IGottaQ]

Eighty, thanks for your reply.
Much appreciated.

 

[Rick3478]

I don't know about 3.55 specifically, but I'd expect the factory to set up hypoid gears for optimum mesh in the forward, thrust direction. They don't expect reverse to be used often or at speed, and may not even check the back sides of the teeth. The pinion is also thrusting against a pretty heavy duty bearing going forward, but pulling on a lighter bearing in reverse, which also may have more case flex.

So in general, I'd demand polished performance moving forward, but not be too concerned with a bit of growl in reverse.