Clunk noise on the 1/2 shift in an A999 trans.

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So a while back, I loosened the front band off a 1/2 turn as was suggested. It definitely helped, but did not go away completely. I was not sure how far I could safely go out with that adjustment before I introduce other problems. From what I understand, the front band being too loose can cause a lazy or non existent 1-2 shift. Is this correct?

I finally got back at this problem this weekend. I dropped the pan, adjusted the bands to factory specs and put it back together with fresh ATF+4. I adjusted the kickdown cable so the lever is almost all the way forward at WOT. I left about 3/16" more pull available. It is no longer a clunk, but It definitely sounds like shift overlap. It now shifts noise free at light throttle and at full throttle but at 1/2 to 3/4 throttle the noise is there.

I will loosen the front band 1/2 turn again this weekend and hopefully I have it handled. What about fluid pressure? Is there any possibility that this could be a fluid pressure problem? I say this cause it is dependent on throttle position. How do I adjust fluid pressure? Can I even adjust it other than with kick down lever?

Cley
 
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89on35s said:
So a while back, I loosened the front band off a 1/2 turn as was suggested. It definitely helped, but did not go away completely. I was not sure how far I could safely go out with that adjustment before I introduce other problems. From what I understand, the front band being too loose can cause a lazy or non existent 1-2 shift. Is this correct?Lazy maybe,but non-existent only when the adjuster falls apart,lol.

I finally got back at this problem this weekend. I dropped the pan, adjusted the bands to factory specs and put it back together with fresh ATF+4. I adjusted the kickdown cable so the lever is almost all the way forward at WOT. I left about 3/16" more pull available. It is no longer a clunk, but It definitely sounds like shift overlap. It now shifts noise free at light throttle and at full throttle but at 1/2 to 3/4 throttle the noise is there.I would adjust it to the max. If part-throttle shifts become too harsh, then the line pressure may need to be reduced. If the car slows down during the 2-3 shift, I would have to say there is something wrong internally.

I will loosen the front band 1/2 turn again this weekend and hopefully I have it handled. What about fluid pressure? Is there any possibility that this could be a fluid pressure problem? Absolutely yes, but perhaps not in the way you might think. I say this cause it is dependent on throttle position. How do I adjust fluid pressure? Can I even adjust it other than with kick down lever? Yes, there is a line-pressure adjuster in the pan. The FSM gives us an adjustment that is supposed to set a proper balance. When you put a shift kit into the VB, then there is always a new line pressure adjustment specified, which the kit supplier has determined will give the best performance with the parts and modifications supplied.
Cley
Click to expand...

Refresh my memory is the rear trans mount in good shape, bolted in tight, and I would bolt that stabilizer weight back on.
 
89on35s said:
So a while back, I loosened the front band off a 1/2 turn as was suggested. It definitely helped, but did not go away completely. I was not sure how far I could safely go out with that adjustment before I introduce other problems. From what I understand, the front band being too loose can cause a lazy or non existent 1-2 shift. Is this correct?

I finally got back at this problem this weekend. I dropped the pan, adjusted the bands to factory specs and put it back together with fresh ATF+4. I adjusted the kickdown cable so the lever is almost all the way forward at WOT. I left about 3/16" more pull available. It is no longer a clunk, but It definitely sounds like shift overlap. It now shifts noise free at light throttle and at full throttle but at 1/2 to 3/4 throttle the noise is there.

I will loosen the front band 1/2 turn again this weekend and hopefully I have it handled. What about fluid pressure? Is there any possibility that this could be a fluid pressure problem? I say this cause it is dependent on throttle position. How do I adjust fluid pressure? Can I even adjust it other than with kick down lever?

Cley
Click to expand...

If the band is backed off so much that the pin in the servo can't reach far enough to apply the band, or so far the strut falls off in the pan it will shift 1-3 with no second gear but it won't actually hurt anything unless it's a solid band instead of a flex band.
A solid band can get jammed between the drum and the case, and that will mess things up.
Solid front bands are not the norm though.

You might just have some sloppy planetary gears and/or lots of endplay of the internals.
 
89on35s said:
Rear trans mount is good. I'll bolt weight back on. What's it for?

Cley
Click to expand...
To prevent clunking,lol
Naw,Sometimes there is a bit of vibration coming from the front of the driveshaft due to the U-joint angle speeding up and slowing down twice on every revolution. And the faster you go the more vibration there might be. The weight stabilizes the trans back end and damps the vibration, while the driveshaft is whipping around.

If the rear mount is good how about the driver's side engine mount? Maybe the engine is popping up and falling down on the shift.
 
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When you adjust the 2nd band, you should first tighten it back up just snug AND counting the turns as you go. Then back it out to where it was, and then add the 2 turns. But there will come a point that it is too loose and then the strut will fall out internally. I don't know how many turns is too loose cuz I have never looked for the edge,lol.
But there is about a bit more than .5 inch of travel on that servo, so I'm guessing you might have that much adjustment available. You'll have to figure it out, or maybe someone who knows will pop in here soon. I wouldn't go that far tho. If you have to go more than 4 or 5 turns from snug, my opinion is that something is wrong inside the trans....... OR OR the clunk is not originating inside the trans.
 
So here is what I did with the bands. The front band (accessible from outside the case) was snugged up to 72in/lbs then loosened off 2 turns, the rear band (accessible from inside the pan area) was snugged up to 72 in/lbs then loosened off 4 turns. Am I right so far? I will loosen off the front band by 1/2 turns and see if that helps now that everything else is right with the world if none of these other things turn out to be the issue.

I will double check my trans mount because I did screw with it a bit when the trans was out but I thought it was good. Motor mounts are good for sure. I will put the weight back on the back just incase too.

The diff has a bit of a clunk but not too bad at all compared to other old Dodge trucks I have run over the years.

Thanks for the comments guys, I will get back to this on Friday.

Cley

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Well, I got back to it on a Friday, just not the Friday I expected. I loosened the front band 1/2 turn and the 1/2 shift issue was almost gone, so I loosened it maybe a 1/4 turn more and it shifts good. I also adjusted the throttle pressure (kick down) cable as near perfect as I can. It is shifting really nice now. Thanks for all the help on this. Now it is leaking like crazy from the shifter or kick down shaft. I'm sure glad I put in a JY transmission. But seriously, it kept me on the road enjoying the car so that's a win.

I did find an A-500 that I will have gone through by a local transmission shop, then I'll put it in over the winter. Hopefully transmission issues will cease after that.

Cley
 
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