Weird sound when in reverse

[jprules32]

When in reverse there’s a weird sound coming from underneath vehicle—possibly from transfer case. Only happens in reverse!— sound does not occur when in drive(or any other gear for that matter). All fluid levels are good. Additionally I checked transfer case fluid levels and there perfect (Fluid color is a light brown/tan). I attached 2 video files and a picture of the fluid color. Any help of what to check or look at would be greatly appreciated! Thanks in advance!

 

[L0jik]

I was going to say thats pretty normal and that I have it too; but you have an automatic not a manual. I know one the AX-15 you always will have this sort of whine when in reverse (due to the reverse gear being non-synchronized). But I'm not sure on the automatic. If it sounds like a grind; there could be something wrong; if its more of a whine noise; it could be nothing to worry about. I'll defer to someone with an automatic.

 

[DWR]

I was going to say thats pretty normal and that I have it too; but you have an automatic not a manual. I know one the AX-15 you always will have this sort of whine when in reverse (due to the reverse gear being non-synchronized). But I'm not sure on the automatic. If it sounds like a grind; there could be something wrong; if its more of a whine noise; it could be nothing to worry about. I'll defer to someone with an automatic.

Same, manual guy here; IDK if the automatics do it too but all of the manuals do. (Ax-15 ones at least.) Doesn’t it have more to do with being dog cut gears instead of being non-synchronized though? It would just be easier to shift into reverse if it were synchronized, at least that is my understanding.

 

[Chris]

Sounds pretty normal to me to be honest. They always whine in reverse.

 

[DWR]

Since you added the videos, it does seem odd to me that it does it while not moving... still waiting on some auto guys to chime in.

 

[jprules32]

Awesome thanks so much for the responses! I didn’t know if it is something I should be concerned about or not but thanks for the feedback!

 

[Mjv]

You might have run over a leprechaun's foot while backing up and he is whining.

 

[steelhd]

In don't know what that is but it sounds like shit. I just drove my auto and it does nothing like that.

 

[Goatman]

Was going to say it's normal for a whine in reverse. Your running on the back side of the diff gears (and standard trans mostly have a straight cut reverse gear.
But that is not the case here. I can't say for sure what it is, but it is NOT healthy.
Chain going in the transfer? Broken clutching in the tranny? Corvid-19 in the driveshaft? It sounds terminal. I would get to your mechanic immediately. If (like me) you are your mechanic I would start by getting underneath and try to isolate what component is doing it. Quickly.

 

[BigIslandJeepGuy]

I'm having that issue now. I'm thinking bad flex plate on torque converter. When I put mine in reverse crawl underneath it, I can put my had on the bell housing and feel it, but not so much on the transfer case. I'm gonna to do a full inspection soon. I've rebuilt hundreds of these transmission (30RH, A904). Another thought was bad cooler flow and is making the transmission pump whine. I'm going to check cooler flow today but I'm thinking bad flex, again I'll do more investigating.

 

[Pirateslane]

I was going to say thats pretty normal and that I have it too; but you have an automatic not a manual. I know one the AX-15 you always will have this sort of whine when in reverse (due to the reverse gear being non-synchronized). But I'm not sure on the automatic. If it sounds like a grind; there could be something wrong; if its more of a whine noise; it could be nothing to worry about. I'll defer to someone with an automatic.

Mind makes a buzzing sound and a whining sound when I’m in motion in reverse when I step on the clutch until I stop moving do you know what that can be? I just spent 4 thousand on a transmission rebuild and it’s still doing it.

 

[L0jik]

Mind makes a buzzing sound and a whining sound when I’m in motion in reverse when I step on the clutch until I stop moving do you know what that can be? I just spent 4 thousand on a transmission rebuild and it’s still doing it.

I have a '98 with an AX-15, it makes a slight whining noise when moving in reverse due to the way the gears are straight cut instead of helical (if I recall correctly). My transmission has less than 10,000 miles on it and it did it from the day I got it. Apparently thats just totally normal for these transmissions. If the noise is ONLY with the clutch pressed while moving in reverse thats slightly odd, but unless its grinding I wouldnt worry about it.

 

[Pirateslane]

Well I took the clutch out because my rear main was leaking everywhere and contaminated it. Replaced both and now when I shut off my car everything grinds to a stop..... I’m ready to drive this thing off a cliff.

 

[L0jik]

Hmmmm, to start with I would see if that happens if you have the clutch pressed in vs with the clutch out to start to narrow it down. If it doesnt happen with the clutch pressed in, its not a transmission problem. What year and transmission is your Jeep?

 

[Pirateslane]

Everything grinds to a stop regardless of the clutch being in or not when the engine is shut off. It’s a 98 with an rebuilt ax15 (needed 500 miles after purchase because the dealership sold it to me with no gear oil in it at all bone dry) that the shop charged me a 100 percent markup ($2000 on top of $2000) for sourcing the rebuild so They also pocketed my 800$ core charge And filled me full of shit . Wasn’t doing it until I replaced the clutch and the rear main because the rear main ruined the brand new clutch that was installed. The one from when I paid the shop to do the rear main and a clutch and they just threw the gasket in the trash and said they did it. When I found it walking by the garage. they just said oh that’s not for a jeep it’s for Chevy read it. (Said amc 4.0 on the packaging even showed it to him and he just acted like he couldn’t understand me and started speaking Spanish.) found that after I already paid them. This is why no one trusts mechanics and everyone is afraid of being overcharged by them. I’ve lost my entire savings due to this jeep and being completely ripped off, all together Including purchase price I’m 17000 something dollars deep on this. So I’m totally ready to drive this thing into a fucking wall.

 

[Pirateslane]

Everything grinds to a stop regardless of the clutch being in or not when the engine is shut off. It’s a 98 with an ax15 that the shop charged me a 100 percent markup for sourcing the rebuild so 4000$ They also pocketed my 800$ core charge And filled me full of shit . Wasn’t doing it until I replaced the clutch. and the rear main that ruined the brand new clutch that was installed. I already paid the shop to do the rear main and they just threw the gasket in the trash. When I found it they just said oh that’s not for a jeep it’s for Chevy. (Said amc 4.0 on the packaging) found that after I already paid them.

 

[Jeep_Noob]

JP, did you ever determine what that noise was?