42RLE makes noises when moving through gears

4.0TJOwner

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I hope someone can clarify this doubt for me. I've never driven a Jeep before other than mine, and by the way I've only had it for about three months. 42rle From the first day I feel that when I move the lever through R N or D it makes a grrrr sound and the Jeep makes some movements as if settling. It's hard to describe also when I accelerate and change from first to second you hear that grrrr for a second it's like a gear sound. It really is very difficult for me to describe this, at the other speeds it doesn't. It only does it again when you reduce from second to first again. I clarify that it is not a knocking sound.
 
You make sure it's full or even a little over full of ATF?

-Mac

The ATF is perfect, good color, level and non-burning smell. The transmission remains at a good temperature as well, measured with a thermometer and it is always around 140f max 150f
 
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Make sure when someone moves the shift lever the lever on the side of the transmission is working.

Have a friend run the shifter and lay underneath and watch.

Is this something you want help fixing? Or do you plan on having a shop fix it?

You comfortable pulling the transmission pan and taking a look? Or pulling the entire transmission?

-Mac
 
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Make sure when someone moves the shift lever the lever on the side of the transmission is working.

Have a friend run the shifter and lay underneath and watch.

Is this something you want help fixing? Or do you plan on having a shop fix it?

You comfortable pulling the transmission pan and taking a look? Or pulling the entire transmission?

-Mac

I don't dare lower the transmission but I do drop the transmission pan and take a look even though I really don't know anything about transmission. What is the lever that speaks to me on the side of the transmission?
 
Question #2

How many miles is on the Jeep?

Question #3

How many miles on that transmission?

Not that it makes a difference to me helping but it may help someone else help you.

132k currently, I have no idea if anyone replaced it so let's assume it's the factory one.
 
I don't dare lower the transmission but I do drop the transmission pan and take a look even though I really don't know anything about transmission. What is the lever that speaks to me on the side of the transmission?

Just get underneath it while somebody up above runs through the gears. You'll figure out pretty quickly which is the thing that is moving.

It sure sounds like a fluid problem, but *If* it's actually a problem inside the transmission it could be the Low/Reverse clutch. It's applied in P/R/N/D1, and then isn't used in the higher gears. ¯\_(ツ)_/¯
 
Just get underneath it while somebody up above runs through the gears. You'll figure out pretty quickly which is the thing that is moving.

It sure sounds like a fluid problem, but *If* it's actually a problem inside the transmission it could be the Low/Reverse clutch. It's applied in P/R/N/D1, and then isn't used in the higher gears. ¯\_(ツ)_/¯

Today I'll get under it to see exactly where it's coming from. But I also don't understand why the car moves as if settling when I move the lever through the gears.
 
Shift lever is on drivers side of transmission- they can have issues at either end as well.

Also make sure it is in 2 wheel high. This needs verified at the transfer case.
 
Today I'll get under it to see exactly where it's coming from. But I also don't understand why the car moves as if settling when I move the lever through the gears.

When you go from P or N to any gear you go from no load on the output shaft to big load on the output shaft. I've never really thought about it before, but the torque tries to get applied to the rear diff but the brakes keep it from going anywhere. So instead it tries to apply it to the other end (back at the transmission) but those are gear-locked so they don't move either. So what happens is the trans mount feels the effect you describe. Or at least I think that's what you're describing. That's how I would describe what my jeep does (well, every automatic I've ever driven) when you go through the gears at idle.
 
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When you go from P or N to any gear you go from no load on the output shaft to big load on the output shaft. I've never really thought about it before, but the torque tries to get applied to the rear diff but the brakes keep it from going anywhere. So instead it tries to apply it to the other end (back at the transmission) but those are gear-locked so they don't move either. So what happens is the trans mount feels the effect you describe. Or at least I think that's what you're describing. That's how I would describe what my jeep does (well, every automatic I've ever driven) when you go through the gears at idle.

That makes a lot of sense, the noise I'm talking about is exactly the same as what it makes when it adjusts itself by changing from P to D or R. That's why I thought it had something to do with it. But when changing from first to second there are no brakes applied so it makes no sense to grrrr again
 
You're in Florida...I suppose it's entirely possible the rear brakes locked up... maybe the e brake is stuck on.

Might want to either push it to verify it rolls or jack up wheels.

-Mac
 
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You're in Florida...I suppose it's entirely possible the rear brakes locked up... maybe the e brake is stuck on.

Might want to either push it to verify it rolls or jack up wheels.

-Mac

In fact, two weeks ago when I braked hard I noticed that one of the rear tires was sliding screaming, I had them corrected and they are ready and checked, this problem has been ruled out.
 
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In fact, two weeks ago when I braked hard I noticed that one of the rear tires was sliding screaming, I had them corrected and they are ready and checked, this problem has been ruled out.

I absolutely don't trust the work of most professional mechanics.

Unless you know them personally and trust them implicitly I would do as Regan and the Russians do...trust but verify...

That and most professional mechanics these days don't know what drum brakes are...

-Mac
 
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