My truck started popping out of 5th under load on a tranny that allegedly had 20K miles on it (bought the truck used). Got a rebuilt tranny, put it in, and it slips out of 3rd. Got ANOTHER tranny and this one is hard to shift and slips out of 3rd. Rebuilder took apart the first tranny and said there was no reason for it to slip out of 5th. I'm beginning to think slave cylinder? Or maybe its the master cylinder.. anyone else have problems like this w/ their Mazda 5spd tranny? This is in a 93 F150 302 2wd.

 

My Mazda 5spd has performed flawlessly, so far. I would think a bad master would create difficulty getting it into gear, not keeping it there. Also, if it were something other than the tranny itself, wouldn't each gear be effected equally?

 

My master cylinder got a crack in it last month and I couldn't get it into 1st,had to start in 2nd and could barely get into any other gears,atleast it was a cheap fix (junkyard).....maybe the gears are worn on your tanny's??!?!

 

The more I drive the thing the more I realize almost every gear is effected. Reverse doesn't seem to be too bad. Its unbelievable that I would have THIS many bad trannys but its also very possible the rebuilder is lying.

Sprocket, did you see the crack or leaking fluid in the master cylinder? If not, how did you know it was bad.

I asked one mechanic who said it was not the master cylinder because that would not cause the tranny to slip out of gear, anyone else have an opinion on that? I'm still leaning toward another bad tranny..

Jerry

 

Ya I saw the crack...I wasn't loosing any fluid just air kept getting in,I sealed it up with some silicone and bleed the clutch and drove it to a machanic....it could posibly be a bad slave,it could be gummed up or stuck in one position...I don't know much about hydrolic clutch systems.

 

when slave cylinders or master cylinders go bad they tend to leak and lose pressure . making it hard to shift into gears and or come out of gears unless you know how to speed shift without a clutch . they WILL NOT cause a trans to slip out of gear period .
if you can drive it in any gear then it isnt stuck with the clutch disengaged which other than a trans problem would be the only way it could slip out of gear.

 

Yeah, what he said.

Take care,
-Chris

 

I asked a few people about it and they said it's probly the gears too,cuz like what Macgyver said,if it's the slave or master it would be hard to get in/out of gears.
Have you taken to more then one transmision guy?I personaly don't trust those little garage shops,I'd just take it to like sears maybe,I know pepboys doesn't do gears...or maybe even the dealership...but thats a last resort.

 

When I had my tranny rebuilt the slave cylinder was leaking-in the used truck lemonaid book its normal to have this problem.

Any chance of it being the shifter or after rebuilding tranny there is some fine tuning to make sure its properly engaged-

My speedometer quit working shortly after tranny rebuilt-changed the speedo gear but didn't really help. Sometimes it would go up then sit at zero-cruise control doesn't work either-vehicle speed senser was changed a long time ago-although speedo worked just not cruise.

So many questions, so little time...

 

I think that I may have a similar problem - bought a used f150, a few days after I got it fluid was low enought that I could not shift.

I know that the truck had not been driven for a while before I bought it. Now in hindsight, for the 2 days that I drove it, it did seem that it got a little 'notchier' until it finally got bad.

My worry is this: could non-use have caused a problem that use would have made show up? fluid has to go somewhere, but can it be low simply from non-use?

 

So here is what I've learned from visiting and dealing w/ 2 rebuilders:

- These trannys suck.. they fail by the thousands
- They have 3 rubber plug seals on the front and back of the shifter turret base (did that make sense). Anyway, they rot/shrink and then the oil from the #3 or #4 gear is flung up around that area at high speed and mists out of the tranny. Sometimes w/ no trail since its a mist and only at speed so doesn't adhere to the truck.
- The tranny runs out of fluid and literally seizes up and then teeth are whacked completely off the #4 gear which is when it typically happens (high speed, towing etc).
- Some rebuilders aren't the sharpest tools in the shed despite how many of thousands they purport to do
- I took the #2 tranny from my truck and had ANOTHER rebuilder take it apart. Found a worn shift fork and used (WEAK) springs. Static length is supposed to be 1", mine were at .75". And they found blueing of the sliders (signs of overheating).
- The rebuilder doesn't think my 2nd tranny will be harmed by the overheated shift rails but its an indication that the rebuild cores are suspect. If yours has NOT overheated then its a good candidate for a rebuild.

- To fix the leak, drop the tranny, remove the turret, and replace the rubber plugs w/ NPT Plugs and lots of RTV.

Hope that helps..

I pick up the other tranny in tomorrow and will install it this w/e w/ a new slave cylinder just in case. Total cost went from $650 to $1250.

Jerry

 

Great info, Jerry, thanks!!

I haven't had any problems at all with my tranny, but I'll remember what you found out. I did just change the fluid in my tranny about a month or two ago, and everything seemed ducky then. I'm not sure why you would have to drop the tranny to access the shifter turret base, though. I have had mine out while the tranny was in the truck (long story about the shift ****).

I guess this reinforces the fact that preventative maintenance goes beyond checking the oil once in a while!

Hmmmm. Maybe I should change the oil in the rear end.

Take care,
-Chris

 

Well I didn't explain that very well:

- you can and must remove the shift level from the cab.
- The shift level bolts to a mechanism that bolts into the tranny (3 screws) and moves the forks/sliders. You can remove that from the cab as well.
- Its the base that bolts to the top of the tranny that incorporates the "tower" that leaks. The "base" is approximately 8" wide by 14" long and is a large plate on the top of the tranny. It is that piece that has the 3 rubber grommets front and back that rot and fall out.

PKRWUD, if you were able to remove that "base" while the tranny is in the truck than you have some serious dexterity!

It is very important to make sure you keep fluid in the tranny. It holds 3.8 quarts of Dexron Mecron III. So, you can either remove the top plug and bend some wire in there to gauge the level if at any point you suspect its leaking. Or, drain it and measure the amount removed and fill it up w/ fresh oil.

92Custom, your truck I'm quite sure lost the fluid through those grommets and was operated dry. That is what kills them. Mine started popping out of 5th but was full of fluid so it failed for another reason but the most common reason is loss of fluid from what these rebuilders tell me (and based on the number of destroyed 4th gears I saw laying around their shops).

Jerry

 

I was low on hydraulic fluid, not tranny fluid. My problem was that there wasn't enough pressure for the clutch to disengage.

but I am still worried about where that clutch fluid went...

here is my new, optimistic theory (I say this with full knowledge that things rarely fix themselves)...

the truck had not been used for a while, and there was air in the fluid. I have driven it a 150 miles since I got it, and essentially bled the system, thus leaving me with low fluid...

yeah right.

I am gonna keep looking for leaks.

 

Jerry-

Oh, okay. I get it.

As far as the tranny capacity, I just changed my fluid, and bought a gallon of DexIII, and a gear oil pump, removed both plugs (drain & fill), and the schit went everywhere when the top plug came out! What a mess. Kinda like a beer bong. Good thing I had such a big drain pan (caught every drop, almost). Anyway, i just stuck the pump tip into the top hole, and pumped until it started to flow out of the fill hole. There was maybe a couple shot glasses of trans fluid left in the gallon container, so I would say that 3.8 quarts is just about right. I poured the old stuff into the near-empty gallon container, and it filled it nearly to the top. I guess mines not leaking yet. Give me a chance, though. I'll get there!

Matt-

Come on, dude. Don't make me slap you.

Actually, clutch fluid (brake fluid) is a natural magnet for water, and water is one third oxygen, so if the clutch master cylinder lid was left off for a while, than you most definately would have gotten air iny your line. but, manual bleeding is absolutely the only way it could have gotten back out.

Take care,
-Chris