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4 Speed issue

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4 Speed issue
True on the shifting. But I've often thought, the length of the stick has something to do with that. If our seats were way down low and the stick were 6" long the shift pattern would be MUCH tighter. Dealing with an 18"-20" stick makes small movement a trip rather than a short walk.
 
IMHO-That 3rd gear 'clank' could well be a classic sign of broken gear teeth. I suggest you drain the gear box and then check the oil for metal chunks with a magnet. You would do well to get one of those long pencil size magnets on a flex shaft, and probe it around the inside of the bottom of the gear box from the drain hole and see what you pull out.
Good luck,
LG
 
Hey guys, me again. The search goes on for my CJ's "clanking" noise. Just how much "play" should there be in the front drive line? I was looking around underneath the CJ again this morning. I grabbed the front drive shaft and there's a little wiggle to it, but what I am more interested in knowing is how much rotational play should there be? There is some there, and you can hear the gears as you twist it back and forth. Kinda reminds me of when I was a kid and the distinct sound my dads old (new then, 1978) Ford truck made when he put it in reverse to leave for work. I would think if it was a front axle issue it would be noticeable in all gears and speeds. Right?

LG, I drained and checked the fluids in both the Transmission and Transfer Case . Nothing unusual, the magnetic plugs had the normal filings. I probed as best as I could but I didn't find any broken pieces in either one.

Danny
 
Where the hubs 'locked' when you did this?
Remove the front DS and go for a drive......
LG
 
Have you made sure the shifter isn't hitting the tub in 3rd gear?
 
Lumpy Grits said:
Where the hubs 'locked' when you did this?
Remove the front DS and go for a drive......
LG
Click to expand...

LG,
Hubs are turned to "4x4", and to be honest, I hadn't checked them. I just knew the Transfer Case was in "2H". This is only the second Jeep 4WD I've owned and the first one was a Wrangler, which was "shift on the fly."

Danny
 
When you first 'lock' the hubs. There's some play till the hub's splines engage.
Like I said-Pull the front DS, make sure hubs are 'un-locked', and go for a drive........;)
Have you confirmed that the shifter is NOT hitting the body tub, like mtnwhlr ask'd?
LG
 
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mtnwhlr said:
Have you made sure the shifter isn't hitting the tub in 3rd gear?
Click to expand...

Yes, that was actually one of the first things I checked. I pulled the Transmission hump inspection plate to see if that was part of the problem. No luck! It seems as though I'm eliminating the cheap possibilities.

Danny
 
Lumpy Grits said:
When you first 'lock' the hubs. There's some play till the hub's splines engage.
Like I said-Pull the front DS, make sure hubs are 'un-locked', and go for a drive........;)
LG
Click to expand...

Ok, that's my next step. I don't understand why the hubs would be in "4x4" and the Transfer Case in "2H". I've probably driven it less than 30 miles since I bought it because I wanted to service everything and find the source of the noise before I drove it regularly. Could something have been damaged with the hubs and Transfer Case in this configuration? I cannot believe I didn't look at that earlier!

One more question LG. Could driving it with the hubs in 4x4 (locked) and the Transfer Case in 2H cause this noise? Or does that even matter as long as the Transfer Case is in 2H?

Danny
 
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'Locked' hubs and 2Hi won't hurt a thing.
LG
 
Lumpy Grits said:
'Locked' hubs and 2Hi won't hurt a thing.
LG
Click to expand...

Thanks, that's a relief! I'm going out to drop the shaft and see if that eliminates the noise. IF it does, what would you suggest next? Replace u-joints and reinstall the DS?

Danny
 
I would first look for slop/play in the slip-spline and then look for ANY kind of play in the 'joints'.
LG
 
Alright, I dropped the front DS. The u-joints need to be replaced. They weren't in terrible condition, but were definitely showing their age. I jumped in, fired it up and pulled out of the drive. Shifted from 2nd to 3rd, there it was, that dreaded sound! I thought, "what the heck, it's a beautiful day. I'm going for a drive anyway!" Well, almost an hour later I pull back up at the house. I get out, go in and my wife says, "so, you got it fixed!" I said, "oh, no, but man did I have a great time riding the dirt roads!" She just rolled her eyes. I did learn something that may actually lead to an answer to this problem though. Purely by accident, as I was riding around I shifted into 3rd gear and put pressure on the shifter towards my right leg. The sound completely went away! I tried this several times, and if it didn't completely silence the sound, it at least changed it. Ideas anyone ?

Danny
 
Ok, at the risk of sounding like a total moron, I'm going to ask. Is that a big deal, as in expensive? And is it something that I can do? One other thing, I noticed that the front DS has been lengthened by 4". Would that have been necessary for the NP435 conversion?

Danny
 
It would be best if you had an experienced manual tranny guy look'n over your shoulder, since this would be you first go at anything like this.

435 mod would be DS changes in length.
LG
 
Pride can be an expensive character flaw! I've learned from experience not to overestimate my capabilities! I will get an expert for this. I know that my time hasn't been wasted in the quest to find the source of this noise. I've discovered routine things that needed to be addressed that could have lead to serious problems. Like the Transmission mount and torque arm. I also learned that I NEVER want to drop and reinstall the skid plate on my CJ by myself again!! Crawling on, in and under my CJ has given me the opportunity to get to know it better! And I have enjoyed every minute of it. Not to mention how helpful the folks on this forum have been. I would have been totally lost and in the dark without you guys being kind enough to read and respond to my post! Please know how thankful I am for the time you have given me!

Danny
 
I know that I can be a broken record, but have you dropped the REAR drive shaft to check the u-joints and spline. Having a sloppy front spline is more common than folks think. While there should be NO slop in the spline in any drive shaft the front shaft is generally engaged at low speeds where a little movement isn't critical. Front shafts wear out their splines quicker than the rear which seems backwards. While the rear shaft is always under strain the front just sits there not doing much. Not doing much allows grit to build up grinding away. A shaft under load creates movement in the grease essentially flushing the joint.

How are your spring bushings? Are they tight? Check the spring plate for tightness. Then there's a warn differential carrier and gears. In the end, how are your axle bearings? I believe you are stuck with the ever unpopular Dana 20 rear end (with the Transmission change you might have a Dana 44 ).
 
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Hedgehog said:
I know that I can be a broken record, but have you dropped the REAR drive shaft to check the u-joints and spline. Having a sloppy front spline is more common than folks think. While there should be NO slop in the spline in any drive shaft the front shaft is generally engaged at low speeds where a little movement isn't critical. Front shafts wear out their splines quicker than the rear which seems backwards. While the rear shaft is always under strain the front just sits there not doing much. Not doing much allows grit to build up grinding away. A shaft under load creates movement in the grease essentially flushing the joint.

How are your spring bushings? Are they tight? Check the spring plate for tightness. Then there's a warn differential carrier and gears. In the end, how are your axle bearings? I believe you are stuck with the ever unpopular Dana 20 rear end (with the Transmission change you might have a Dana 44 ).
Click to expand...

Hedge,

I haven't checked the rear DS yet. It's next though. As far as the suspension goes the springs are as straight as a board! Plus, the shocks are not the best either. I don't think there is any sign of an arch in them whatsoever! A 2-2.5" lift (complete kit, including serviceable shackles) is in its near future. Not sure which brand though. I spoke to a mechanic this morning. I described what was going on with the noise. He is going to check the Transmission out for me that way I can eliminate it one way or the other. Yes, I believe that I have the AMC, Corporate 20 rear axle. The center section is completely round. Not sure what the front is, I haven't really looked at it to identify which it is.

Danny
 
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Danny-Find a local Jeep CJ club near you ASAP.
Find out who they suggest for a drive-line mechanic.
Trust me on this.........
LG
 
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