Help! Shifting Problem in my Manual Tranny -ideas?

[Kirby N.]

Any help would be appreciated. I swapped out my a4ld after a blowing a few a4lds for a manual. The swap went smooth and I have been driving it for 8 months or something. The only problem is that it is difficult to get the tranny into gear from nuetral when the truck is
1. Warmed up
2. At a dead stop

It will go into gear fine if I am rolling or if it is right when I start it up.

In the swap I replaced all the slave/ master cylinder hardware and plumbing so I do not think this is the cause.

I used the used clutch from the donor vehicle because it looked to be in good shape, I also used the flywheel and pressure plate from the donor for the same reasons.

I am completeing my swap by putting in a manual tcase too in the next few weeks and I would like to take care of the shifting problem if it is simple.

Please help! Thank you!

Kirby

 

[Doug]

How many miles are on the transmission? If it's got a lot of miles it's possible there is some resistance internally. I've also heard of people having problems with cut fly wheels and the clutch not fully disengaging but so far i havent experienced anyissues. I suppose it's possible there is a problem with the throw out bearing or possibly the master cylinder. If i was you I'd try bleeding the clutch and seeing if that makes a difference. If not get a quart of lucas oil stabalizer and some mercon V and put that in. I'm running that in my truck right now and it helps the transmission shift alot smoother.

 

[Bronco638]

KN,
When you say it won't go into gear, from neutral, when warm and at a dead stop, you're obviously referring to first gear, right? If so, it sounds like it might be the first gear syncronizer. Does it shift OK into the rest of the gears (once moving)?

Try this, just before you reach a dead stop (approaching a stop light, stuck in traffic, etc.) , shift into first. Because the tranny is still spinning (interally), it will allow first gear to engage the internal driveshaft when they are spinning at the same (low) speed. For first gear, it should shift into gear between 10 and zero MPH. The slower the better to keep from actually grinding the gear teeth. If this works consistantly then it's the synchro.

The reason it may shift OK while cold it the gear oil is still thick and possibly 'assisting' the syncro to engage the gear.

Hope this helps - Dave.

 

[Kirby N.]

Hmm. Ok. The tranny has alot of miles on it, but it was rebuilt recently. I might try bleading the clutch and using that mercon 5 stuff before I take the tranny completely out. Thank you.

It won't go into any gears from a dead stop. When moving it goes into all gears fine with no grinding. It is not teribly bad. I can get it coaxed into gear from a dead stop if I have to, but I usually just put in gear before I stop. It never grinds or sounds like a synchro is gone, even when I do get it to go in from a stop.

Once moving it shifts excellent with no grinding in any gears. Does this point to the clutch or flywheel- Any thoughts Doug?

 

[Kirby N.]

I forgot to say THANK YOU! so uhm, THANK YOU!

 

[Doug]

The symptoms you're stating really point to the slave cylinder. Try bleeding the clutch, if it goes away and comes back it's definantly an issue with the slave cylinder and will need to be replaced.

 

[Bronco638]

KN,
Sounds like Doug diagnosed the problem correctly. If you cannot get any gear at a dead stop, then the clutch disc isn't completely disconnected from the flywheel/pressure plate. Could be clutch master cylinder or the slave cylinder. Listen to Doug, he knows his stuff, I'm just rambling............
Dave.

 

[Kirby N.]

OK. I will try bleeding it when I swap out my push button Tcase here in a few weeks. I remembered that I got the idea from the guy I bought the tranny and the swap parts that it was having some slave cylinder problems (fellow board member), so that is why I replaced everything in the slave cylinder's path.

Any chance it could be something to do with the pedal assembly or the tranny? I used both of those from him, and I know that he swapped them into his truck as well. If the pedal assembly was out of a Bronco 2 would that cause it? Maybe not as much throw in the pedal or something?

Oh, for explanation sake I swapped from an a4ld to this tranny 8 months or so ago.


Thanks Again!!!!

 

[unclemeat]

When you replace the slave cylinder replace the throw our bearing as well. You may also try changing the gearbox oil, It may be contaminated with water.

 

[Kirby N.]

I haven't been in any water since I swapped in the Tranny. I just put the tranny in with a new slave, master cylinder, and Slave cylinder so I hope I don't have to replace my new one. I hope bleeding it will fix it.

 

[Kris Guilbeaux]

Ok I know your Problem and it is the Clutch and Fly wheel it has heat cracks on the Fly wheel that is Why it does it when the Truck is Warmed up. Had this Prob on my Navajo.

 

[Kirby N.]

Kris,
Thanks man. Your reply on Pirate is what got me thinking it was just the clutch and not the tranny.

I have officially decided that it is the clutch. It doers not help to pump the ****ch and it only does it when it is hot. I also spoke to a guy here locally and he said diaphram-type clutches do this when the clutch plate gets alot of miles. Apparently, those fingers that rest on the throughout bearing get worn and fatigued and do not respond as well to the slave when they get hot. I guess this is especially bad because you can not adjust for it with hydrolic clutches. SO I have decided it is either the fingers or surface cracks on the clutch plate, possibly a warped flywheel- either way I need to pull out the clutch, get the flywheel tested and put a new clutch in.

Right now, I do not have the time to put it in or the $192 (!!!!) for a new clutch, so it will have to wait a few months.

Thanks for all the input. I will follow up when I get it fixed.

Kirby

 

[Brock94]

I just want to add a thought, since I had similar problems with my 5 spd. I never really noticed whether it was worse/better warm or cold, but I did have trouble getting it to go into first when sitting at a stop light if I did not put it in gear before coming to a stop. It had this problem since I bought the truck last February and I finally decided to bleed the clutch. I tried to follow the bleed procedure in the Haynes manual, but there was no improvement-- in fact the problem got worse.

It turns out that the factory manual has a much different bleed procedure from Haynes that works much better and solved the problem in my case. (I did have to repeat some of the bleed steps a few more times than the manual called for and I needed to coax my wife into the driver's seat to work the clutch.)

Let me know if you don't have the factory manual or know the procedure and I'll try to post it here.

Also, if you've been grinding gears at all, you might want to drain the tranny to get out any metal filings. I replaced the fluid with Mobil 1 Synthetic per advice on this site and it's amazing how much more smoothly it shifts.

 

[Kirby N.]

Thanks Brock.

Hmm. I do have a factory manual. I might put that mobile 1 in there. Was it Mobil 1 Synthertic ATF or what? I have a feeling that the longer I let this go, the more risk I have of jacking up my tranny. I am forced to grind ever so often and metal shavings sound bad!!

 

[Brock94]

Yeah, I couldn't believe all the metal filings stuck to the magnet on the drain plug, I've been thinking about draining and refilling it again just to be sure I got them all out. (This was after quite a bit of grinding before I did the clutch bleed.)

Yes, I used Mobil 1 Synthetic ATF per advice I read elsewhere on this site and I did notice a big difference-- and it's only about $10 for the amount you need (of course I used new DOT-3 brake fluid for the clutch bleed, ATF was for the transmission case-- sorry to state the obvious, but want to avoid any possibly disasterous miscommunication.)

For the factory-manual clutch bleed, you'll have to get the special hydrolic-line disconnect tool from a parts store. I've read about people disconnecting the fitting with a couple screwdrivers, but it seemed like a lot of trouble to do so. The biggest difference in the factory bleed procedure is that you disconnect the line from the tranny, use a screwdriver to release the check-valve in the end of the line and have someone press the clutch a couple times to bleed the line.

Oh, there were a couple things I did differently-- I repeated the bleed step for the line several times more than specified in the manual to be absolutely sure all the air was out. I had to refill the reservior a couple times-- during this procedure do not put the diaphram and cover on the reservior as it will prevent adequate fluid flow. Also, the last two or three pushes of the clutch, I told my wife to stop pushing when she felt resistance, then I let the check-valve lock mid-stroke just to be sure the fluid didn't run out and let air in. It's important that your assistant stop pushing when they feel resistance as you let the check-valve lock, because if they do not they could ruin the master cylinder by putting too much pressure on the system.

The factory manual also tells you how to fab-up a tool to measure the throw-out bearing travel to see if it is enough. I didn't bother since my results from the bleed were so good.

 

[bills]

Kirby? How'd this pan out? Are you still around?

 

[Kirby N.]

Um, Still driving it!! I decided it was the clutch diaphram. I have been told that with older clutches (mine was used when I put it in) the diaphrams become weak especially when hot and do not release the clutch entirely. I really can't afford the $200 for a new clutch, even though I know it needs it. I have another tranny and motor that I might just throw in instead.

I did bleed it a couple of times with no result.

Kirby

 

[bills]

Damn, been almost a year now, sounds like your truck is doing OK...

My x is showing some of the same problems and Im worried because Im moving next month... and have to drive it pretty far...