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Sundance 6g72
06-05-2012, 12:05 AM
so i got hold of a shadow cable and swapped my 1g neon cable out for the shadow cable. still has a hard time getting into third.

trans in question is a a543 (1993)

from the driving ive done, it seems that the tranny favors higher rpm (2500+) to get into third along with shifting quickly. it think its silly to shift that fast during day to day cruising but its required.

when i try to shift at say 2200rpm in a relaxed fasion (just like any other person) it tends to either grind or go in just fine only to pop out when i release the clutch a moment later.

it also pops out if im sitting idle and put it into third.. right when i start to let the clutch out, it pops out.

1st 2nd 4th and 5th have never given me problems ever never ever never never. lol. this is strickly third gear being a pain the ---.


this all started about a year and a half ago when a failed power shift from 2nd to third resulted in a horrible gear grind. i was always able to upshift fine and down shift (if i double clutched/rev matched) but this is different/worse. i thought it was the shift cable because after i did my engine rebuild, the shift cable was stretched or something because it was pulling way to far into third. i replaced it with a 1g neon cable which tightend up the shifting (felt great) but third gear had the problem i described above. naturally i thought it was just because i was using the wrong cable. swapped in a shadow cable and i have the same problem but with a looser shifter. i almost liked the neon cable better.


when i compared the 1g neon cable to the shadow cable, the shadow cable had more throw in each direction BUT it should be noted that 1g neon cable seemed to have just enough throw to push the trans into gear all the way. I shifted into third and then disconnected the cable and the trans didnt want to go into third any further than where the cable put it. making me think that the cable was never the problem in the first place.



(ALL of the above is talking about the big bushing cable, not the crossover. the crossover has been adjusted over and over making things worse or better but never perfect. the crossover appears to be in steller condition as well)


im starting to think i had a syncro problem and now have a syncro and shift fork problem. i never had the popping out of gear problem until very recently.. its ahrd to live with. i can live with a bad syncro.

anyways, how do i go about checking the shift forks? from what i know, i can do it without pulling the trans. this seems like a logical first step.

Sundance 6g72
06-05-2012, 02:34 AM
http://www.turbododge.com/forums/f4/f22/49621-a555-replacing-shift-fork.html

identical problem

135sohc
06-05-2012, 04:06 AM
On the sliding collar that the fork moves the area where the gear engadges into it is slightly undercut to help 'suck' the sliding collar and gear into a meshed position. If the fork is bent (highly unlikely but not impossible I suppose) and/or the plastic fork inserts on the 3rd gear side are trashed or really worn down to tissue paper thin then it could allow the fork to not fully push the sliding collar over enough and 'suck' everything together. That muffled metallic crunch/ziiiiiing sound is the sliding collar and the speed gear hitting eachother at different speeds. Another problem could be the synchronizer struts/keys have become dislodged somehow and can cause all sorts of issues. Because they are what push out on the brass blocker ring and make contact first to speed match the shift and keep things from grinding.

shifter housing is 6 bolts and the 3-4 shift fork is right there in the center. You can see the front fork pad if you look around everything. To service anything the side of the transmission has to be opened up and everything 'unloads' from it like a nesting doll set.

Sundance 6g72
06-05-2012, 10:55 AM
can i verify the shift forks are alright by removing just the 6 bolts to view everything? what about third gear syncro.

i think the syncro might be pretty warn but back in the day, 2nd gear got way way wayyyyy more abuse than third yet third let loose in one shot and not slowely over time. my reasoning for thinking it could be a shift fork that went from working to broken in one shift.

135sohc
06-06-2012, 12:54 AM
Yes you can sort of see them. There going to be underneath all the shifting rails and all that bs so theres not alot to see but enough to maybe get an idea of the internal condition. The 3rd gear is hidden underneath everything but if you can push the fork over into 4th the edge of the gear will be visible and you can see how screwed up if anything it is. Without taking the guts out and really giving everything a good inspection theres not much you can do besides look and see if theres any obvious damage like oil thats full of metallic garbage.

Sundance 6g72
06-06-2012, 01:11 AM
so from reading your previous post, i can pull the whole gear set out of the trans by removing the side cover? i dont actually have to pull the tranny from the car? that sounds to easy.

also, where can i get new shift fork pads, shift forks, and gears/ syncros

oo and one more thing, internals from an a523 will go into my a543 correct? what about neon 5spd trannys? i bet that one is a long shot.

Sundance 6g72
06-09-2012, 04:25 PM
so can i pull the "gear assembly" out without pulling the trans or what?

135sohc
06-09-2012, 10:57 PM
so can i pull the "gear assembly" out without pulling the trans or what?

yes.

http://www.turbo-mopar.com/forums/showthread.php?66296-1990-A-568-FSM-Scan-4-Download-in-Zip-format <<<< look here

Sundance 6g72
06-10-2012, 12:07 AM
cool thanks. i was looking at that but wasnt sure if it required the trans being out of the car or not. that makes things easier.

before i tear into this, i know i am suspecting one of the following

- bad third gear syncro
- bad shift fork pads for third gear
- bent shift fork (unlikely?)

id like to know where i can source those parts so i can keep this job as short as possible. im still a little sketched out aboutt he idea of tearing into the trans. i guess if i can tear a motor down and rebuild it along with tuning it, i should be able to replace a part in the tranny..

135sohc
06-10-2012, 12:42 AM
523 parts are the same, year for year the 543 is the same internally as the 523. The bellhousing is the only difference.

The sad thing with these transmissions is that there are no new parts available from chrysler and the aftermarket has no following either. Your going to probably have to find a parts donor in better shape to borrow anything you need to replace.

I do have new stock replacement pads available for the 3-4 fork and that small retaining ring that keeps the 5th gear and synchronizer retained onto the pinion shaft available as new replacement if so desired.

Sundance 6g72
06-10-2012, 02:12 AM
whats the price on the pads for 3rd-4th?


there is a 523 in the local yard near me. what special tools do i need to tear into the trans and pull the gear assembly out?

135sohc
06-10-2012, 02:43 AM
$2.75 each. add $1 for postage

Make sure its a 3.77 final drive transmission. 90-91 transmissions are a different can of worms and while not totally unusable for your purposes there are some major and minor differences.

drift punch, hammer, 3/8" drive 10mm socket and assorted extensions w/ratchet, 27mm 1/2" drive 6 point socket w/breaker bar. red & blue loctite, anerobic sealant and a pair of retaining ring pliers not snap ring pliers. big pile of clean rags, razor blade or two and 3-4 cans of brakecleaner. The nut on the input shaft is torqued tight as **** and everyone has their own way of dealing with it.

I use this tool set with the jaws heavily ground out to pull the sealed bearing off the end of the shaft. http://www.harborfreight.com/14-piece-gear-puller-set-30305.html its a POS but works ok.

Ondonti
05-03-2013, 12:33 AM
What was your result of all the fixing?