Possible Syncro Problem

[marie]

Hi guys, it's been a while.... I need some help diagnosing a shifting problem. Well, actually, it's not shifting, that's the problem. For starters, this is an 88' Comanche, 4.0, manual tranny, yes I am a girl and yes I do all my own work and have for many years, even successfully, LOL!  I'm guessing the syncros are shot, but I'm not certain and transmissions are not my specialty. It's always been a little stiff going into first or second gear when cold, nature of the beast as I am told. Though I have noticed it getting a little worse lately. I recently replaced my clutch, plate and internal slave cylinder and all was working well after the repair and shifting was like butter. That was a month ago. The last several days first, second and reverse started getting tough. Today it got worse and I had to drive some back roads in second gear home. Thank goodness I wasn't far from home. I'm fairly certain the clutch is disengaging fully. It was bled properly when I changed the clutch assembly. When it's not running I can change gears easily, this is only when it's running. Third and fourth gear seem to be ok. I'm guessing my (probably) 28 year old syncros are failing. Does anyone have any suggestions on anything I can check or test before resorting to taking the transmission out..... again! Though I'm 125 lbs of stubborn ornery, dropping the tranny is no easy task, on the ground with a standard hydraulic jack...solo, no matter how big you are. I did pull my engine and dismantle it by myself and that felt like a piece of cake compared to dropping the tranny without a lift... I will admit I did enlist the help of my rather large 6'3"/220lb military son to wrestle the tranny off the spindle and back on, he is not available right now to help. He is keeping up the family tradition (which started with me, there are no grandpas or uncles) and he is a crew chief and a jet mechanic in the Air Force. Sorry, I can't help myself when it comes to bragging about him. When we work on cars together, he calls us master and blaster... :-) 

 

got any suggestions? Many thanks in advance if you do!

[yxmj]

Start simple......drain the old fluid and fill it up with synthetic 10W-30.........that might give you some drivability......but unfortunately once they are gone.....they don't re-grow  :thumbsup:

 

. :MJ 1: .

[Eagle]

Does it grind shifting into 1st and 2nd? Does it pop out of gear when coasting/decelerating? If "no" to those questions, the problem likely isn't the synchros, it's probably that the clutch isn't fully disengaging. Try bleeding it again and see if that makes a difference.

 

Also, what are you using for transmission lube? I have an '88 Cherokee 4.0L. Despite the BA 10/5's bad reputation, mine has lasted 287,000+ miles and stil shifts well. It IS hard to shift into 2nd gear, especially when cold, but otherwise it works fine. A couple of tricks I've picked up, which may or may not work for you: if it doesn't want to shift into 1st from a stop, shift into reverse and then into 1st. Going from 1st to 2nd, either "granny" shift it (like only rn it up to about 1200 RPM in 1st before shifting) or shift at exactly 2000 RPM. And don't rush the shift -- it's not a drag race transmission.

[marie]

Thanks for the responses!

 

Eagle, I believe i have a Renix transmission and I'm not sure if that is a BA 10/5? I'm pretty sure I used 75W90 last time I changed it, I used what was in the manual and I don't have the manual handy at the moment. It's not that the gears are grinding, it's that I can't get the stick into the gear positions period. I can't get it in reverse to even retry first gear. :cry:  I don't recall it popping out of gear upon deceleration for coasting. However I can shift it easily when it's not running, which is why I assumed it was the syncros. But like I said I'm not that knowledgeable about transmissions. I will change the fluid tomorrow and re bleed the slave cylinder (if it doesn't rain like they say it will). Don't worry, I have never treated the transmission like a dragster, I baby this truck because it's all I have, and I kind of like it. We understand each other, even if she is a bit temperamental sometimes.  ;)

 

So, what are the pros and cons on switching to synthetic vs the 75W90?

[omega_rugal]

Not the synchros but definitly needs to be dropped and serviced...

[marie]

PS, I just called the driveline specialist in town just to see what it might cost to have the syncros replaced. They said they won't even touch my Peugeot transmission. They said they never work right if they are rebuilt even if you can find the parts. They also said replacing it is even worse. Please tell me this isn't so...... I just put a new engine in 5 yrs ago, the front end suspension and steering are completely rebuilt, new clutch and new tires in the last couple of months... all done by me  :cry:

[Eagle]

Your synchros aren't bad, so put those fears to rest. If the synchros were bad, you'd be hearing a symphony of scary-sounding noises when shifting, and shifts would be very harsh and "notchy." I'm pretty certain that what's happening is that the clutch isn't fully releasing. I would try bleeding it again. You could also try changing tranny juice. The factory spec for that transmission was 75-90 GL-5 gear lube, but I think the factory later backed off of that because of the sulpher compounds in GL-5 lubes. However, that's more of an issue with the AX-15 transmissions, it may not be as big an issue with the Peugeot BA 10/5.

 

The next time I service mine, I'm going to use Pennzoil Synchromesh transmission oil. It was formulated specifically for newer transmissions like the NP3500/3550, but I've read reports that it performs favorably in the BA 10/5 as well. In my '88 Cherokee, I've also been running a molybdenum additive. It's no longer available from the source where I bought mine, but there used to be an on-line place called, (IIRC) "Mr. Moly" that should have it. Or -- go to an on-line vendor of firearms reloading components and buy micro-fine molybdenum powder and mix your own. That's what I'll be doing the next time. Moly powder is super slippery, plus it has an affinity for metals so it sort of plates the parts ir comes into contact with, and greatly reduces friction.

[marie]

Thanks Eagle! Don't know if I can get the Moly by Saturday, though I live in NV and there are gun stores everywhere. I might be able to find it local. At the very least I will drain and replace the fluid with Pennzoil Synchromesh and then change it again when I get the Moly  powder. If mixing myself, how much powder would you recommend adding to each quart of fluid? I will bleed the system too and report back Saturday. I'd do it tomorrow but it will be raining hard tomorrow and I don't have a garage..... Does that make me a street mechanic rather than a backyard mechanic???  :yes: 

[marie]

Got the Pennzoil Synchromesh and the Moly powder, changed the transmission lube. The old stuff still looked good and there wasn't much shavings on the magnet, always a good sign. Also replaced the bleeder valve, as I noticed a drop of fluid on it even though it was tight, and bleed the system. I'm glad to report she's shifting like butter once again. \m/ This transmission has over 250,000 miles on it. The speedometer broke about 4-5 years ago when it was at 239,000 so I'm guessing at the mileage, though it's probably higher than 250K. I think the bleeder valve was the issue in that it wasn't seating properly. If any fluid can come out, air can get in. I was fooled a little when I initially looked in the reservoir and the fluid level looked good, so I thought everything was good with the clutch system. My Comanche and I will grow old together after all. :)

 

A word to the wise about the Pennzoil and Moly. I used a tablespoon, which is an ounce by volume, in each quart of Pennzoil. Molly is very heavy and it settles in the fluid almost instantly and does not want to stay suspended even when mixed thoroughly. Even after I had put the pump on bottle, I had to keep shaking the bottle. I'd put 10-15 pumps in the transmission then tilt the bottle back and forth several times. It takes longer but it's the only way to insure you're getting all the Molly in the transmission. Also, wear gloves, a dusk mask and safety glasses when working with Moly, it's poisonous. Especially when  you are under your truck and on the ground like I was, waiting for it to spill out of the fill hole. If you get it in your eyes, it's a trip to urgent care, it's even finer than graphite powder. Tomorrow I get to work on my Grand Cherokee... aka "the beast"

 

Thanks for the advise everyone! Every time I finish working on my truck I hear the same song in my head... Highway to Hell..... It's my road trip song \m/ 

Someday I'll be done enough with repairs to lift it and paint the body.... It's ok, I can dream, I can dream.... :thumbsup:

[Eagle]

Good news. Thanks for the follow-up.

[marie]

Hey guys, I'm back.... You should imagine the jaws theme song as you read that.

 

So, I seem to be getting air in the system from somewhere. I have had to bleed the system twice now since I changed the gear lube and bleed it a few weeks ago. The last time I bleed it quite a bit, used more than half of a big bottle of Dot-3 to be sure there was no air in the system. Checked all the connections to be sure they were tight. It seems to be ok for about 5-7 days, then it goes back to needing to be bled. It's obvious it's getting air somewhere, but the fluid doesn't get low so it's not leaking fluid anywhere. I had to replace the bleeder as my son mashed the one it came with with vise grips because he stripped it (just the nut portion not the threads) trying to initially loosen it to bleed it when we first installed it all. This is actually the second replacement bleeder as the first one was too long and didn't seat completely. Is it possible that it's getting air through the threads, should I try some teflon tape? Or would that not hold up to the Dot-3? The only connections for the fluid are at the master and just outside the transmission by the bleeder, right? Should I try another bleeder? Maybe from a jeep dealer instead of Napa? They are tiny, 1/4". Big trouble comes in small packages, I know, I'm a small and I am definitely trouble! Let me know your thoughts!  :thumbsup:

[Eagle]

If the fluid level in the [clutch] master cylinder isn't going down, you're not losing fluid. If you're not losing fluid but the clutch isn't working, the fluid almost has to be gradually weeping past the seals on the piston in either the master cylinder or the slave cylinder. Unfortunately, I don't know of any way to effectively test to isolate which is the likely suspect.

 

One other possibility is that air is being allowed in during the bleeding process, and then takes a few days to migrate to where it interferes with clutch operation. (And I'm not sure if this theory makes any sense.) How are you bleeding? The reason I ask --

 

An old friend (even older than I am, which those who know me may find hard to believe) is a retired AMC/Jeep service manager. He retired when the dealership he had worked for since he was 16 years old was sold. Many of his old customers prefer to bring their AMC cars to him rather than find somewhere else to service them. I went to visit him one day and found him under an AMC Hornet, swearing a blue streak. He was trying to bleed a clutch -- by himself. I was amazed to see a professional doing what he was doing, but there he was ...

 

His procedure was to fill the [clutch] master cylinder, sit in the vehicle and vigorously and rapidly pump the peddle several times, then crawl under and open the bleeder for a few seconds. Then close the bleeder, and repeat the process. I told him I was pretty sure he was just foaming the brake fluid, and I asked him to try it the way my grandfather taught me. I sat in the vehicle, with him underneath. He opened the bleeder. I pushed down on the peddle -- slowly -- until it stopped, and which point I told him to close the bleeder. Then I let the peddle up, pumped it slowly about three times, let it up, and told him to open the bleeder. Repeat process maybe half a dozen times.

 

That did it. If there's any air at all in the system, too much pumping turns a few big bubbles into a gazillion little bubbles. Over time, they reunite into big bubbles, and that's when you get a spongy peddle.

 

At least, that's my story and I'm sticking to it.

[HOrnbrod]

That retired AMC/Jeep service manager sounds like an idiot. No wonder AMC went under.   :yes:

[Eagle]

That retired AMC/Jeep service manager sounds like an idiot. No wonder AMC went under.   :yes:

 

Actually, he's a top-shelf wrench, and one of only two people other than myself that I allow to work on my vehicles. That's why I was so astonished to see how he was trying to bleed the clutch.

[Marine1Texas]

I have had the clutch master cylinder intake air from around the shaft of the peddle (that area get a lot of wear). When ever I change the clutch I go ahead and change everything.

 

I agree with above. However I do bleed my self with one person. I open valve the push slowly to floor then I put my stick in place, close valve, pump 2 times slow, then I open valve and slowly go to floor then put stick in place, close valve. That is how I learned to do it by my self, and never failed. it takes about 5 minutes. I always try to bleed air out before I hook up the new master clutch cylinder and line.

 

The BA10/5 has problems of pushing apart in the middle, because of the soft metal. I have had a BA10/5 last 200K. Once they start to go out look for a AX15 and fill it up with slick 50 till you get your ax15 or it go's out.

[cruiser54]

It's true. Those systems were a bear to bleed.

 

After the initial bleeding, we would pump the pedal 50 times without bleeding and walk away for 15 minutes. Come back, it's fine. 

[marie]

Hey, thanks for all the pointers. I did have another person in the truck pushing the peddle while I worked the bleeder. However I did not have them pump a few times in between bleeds. I'll give that a try before I think about replacing the line.  The master is only a couple of years old, so hopefully it's not getting air at the plunger, but I'll keep that in mind if all else fails. 

 

As for the guys who do it solo with a stick, you have to give them a lot of credit for not just throwing their hands up and saying, "no one else around so I can't do it". I do most of my work on my truck solo and have learned to come up with some tricky mechanical advantages when I lack the physical strength for some part of it. There's nothing a good breaker bar and a length of pipe can't handle.... I also do a lot of the work solo because no one wants to here me cuss and throw wrenches...  :rotf:

 

I'll report back in a week or so, it'll be that long before I know if it all worked. in the meantime  :cheers:

[cruiser54]

Hey, thanks for all the pointers. I did have another person in the truck pushing the peddle while I worked the bleeder. However I did not have them pump a few times in between bleeds. I'll give that a try before I think about replacing the line.  The master is only a couple of years old, so hopefully it's not getting air at the plunger, but I'll keep that in mind if all else fails. 

 

As for the guys who do it solo with a stick, you have to give them a lot of credit for not just throwing their hands up and saying, "no one else around so I can't do it". I do most of my work on my truck solo and have learned to come up with some tricky mechanical advantages when I lack the physical strength for some part of it. There's nothing a good breaker bar and a length of pipe can't handle.... I also do a lot of the work solo because no one wants to here me cuss and throw wrenches...  :rotf:

 

I'll report back in a week or so, it'll be that long before I know if it all worked. in the meantime  :cheers:

Try the 50 pumps and walk away trick first. 

[64 Cheyenne]

Did you use Mopar parts when you replaced the master/slave?

[marie]

Did you use Mopar parts when you replaced the master/slave?

 

I get all my parts from Napa, I can't afford dealership parts. 

[marie]

I thought I posted a final report here, but apparently I didn't, my apologies.  I kept getting little bits of air in the system and finally I replaced the line between the master and the connector on the slave cylinder, bled it with my handy dandy Mityvac (love that thing). And all was well for several weeks. Then..... it started again, only this time the fluid level just keeps dropping in the master, it's not actually sucking air in that I can tell. I was baffled, so I wrapped paper towel pieces around every connection, the master itself and even under the plunger on the inside of the cab and tapped them all in place, then drove it for a week. Could not find a leak. Then I put newspaper under the bell housing and pumped the clutch, yup you guessed it, fluid on the paper... :wall:

 

That means the brand new slave installed with the new clutch went bad, right?  The slave that's inside the trans is a closed system, right? I mean the bleeder and the line to the master that hang out outside the trans are the only places the slave can leak from that I can see or imagine. But why would it go bad 6 months after being installed. If it was bad from the factory, wouldn't it have leaked from the get go? Is there a seal somewhere in the part that is inside the trans? I'm a little horrified because I don't have a lift and my truck isn't lifted. So dropping the  tranny is tough on the street. 

 

Any diagnostic suggestions I have overlooked? 

[cruiser54]

Replacement parts are hit and miss these days with most of them being made outside our country.

[marie]

Replacement parts are hit and miss these days with most of them being made outside our country.

 

So, is my diagnosis correct then, that the slave itself is leaking internal to the tranny? if so, where does it actually leak from, there aren't any fittings on that part as I recall?

[cruiser54]

 

Replacement parts are hit and miss these days with most of them being made outside our country.

 

So, is my diagnosis correct then, that the slave itself is leaking internal to the tranny? if so, where does it actually leak from, there aren't any fittings on that part as I recall?

 

It has moving parts/seals. 

[64 Cheyenne]

 

Did you use Mopar parts when you replaced the master/slave?

 

I get all my parts from Napa, I can't afford dealership parts. 

 

 

 

Replacement parts are hit and miss these days with most of them being made outside our country.

 

This^^^

Chinese Replacement Auto Parts = CRAP

Sorry