Just rebuilt trans. Non-syncronized?

[VDub2625]

I have a question... I just got my trans rebuilt, and I can't remember if it was syncronized (it's a winter car and it's been a while since I've driven it). It seems to take a large amount of time to downshift, and it goes through each gear until it finds the lowest one. It's a 1997 SOHC with the 5 speed (5r55e) IIRC. Isn't this a non-syncro trans? I wanna make sure I didn't get screwed by someone slapping the wrong trans in... Thanks!

 

[Glacier991]

Automatic transmissions do not mesh gears... they connect gears through clutch sets.... but the gears used are always engaged with opposing teeth... hence there is no "synchronization" required to match the relative rotational speeds of gears in order for them to engage (synchro).

 

[VDub2625]

I do not know a lot about automatic transmissions (the last "big frontier" for me, I just can't seem to grasp it through explanation, but everyting else about a car, I know ), but I do know Ford started using "non-syncronized" transmissions in Tauruses in 1995 (transmissions that employ direct gear selection vs. needing to cycle through gears when accelerating). I thought the Explorer had this in the 5 speed, but I could be wrong.

Either way, there appears to be quite a delay when accelerating anyway, when flooriing it from a rolling stop, it can take anywhere from 5-7 seconds until it FINALLY settles on a gear. Also, it has a studder at mid-throttle takeoff and again at 60mph.

Something else catches me as weird, too. The engine dosen't seem to "match" road speed and acceleration. It almost feels like the engine dosen't accelerate at all, but rather just stays between 2.5-3k RPM, no matter road speed.

Guess it goes back in

 

[VDub2625]

Ok, this is what I meant by non-syncronized. Directly from www.realtcca.com, the Taurus Car Club of America site. Maybe someone can provide me with some technical insight into which kind of system the Explorer 5 speed uses. Also, I'd like to know how to physically tell the two transmissions apart, if someone can help there

AX4S - Synchronous
Example 1: Cruising at 25mph (3rd gear), you floor it, it downshifts to 2nd gear briefly, then into 1st.

Example 2: Full throttle acceleration from a stoplight to 35mph or so, then let off the gas. The transaxle will up-shift to 2nd gear very briefly, then finally into 3rd gear where it needs to be.

In other words, it has to shift in order 1-2-3-4 and 4-3-2-1

AX4N - Non-Synchronous

Example 1: Cruising at 25mph (3rd gear), you floor it, it skips second and downshifts directly to first.

Example 2: Full throttle acceleration from a stoplight to 35mph or so, then let off the gas. The transaxle will upshift directly to 3rd gear, skipping second.

In other words it can shift how ever it wants 1-3, 3-1, 2-4, 4-2, etc..

The AX4N is a more efficient transaxle. The ability to skip un-needed gears helps reduce wear and tear. Mechanically, the AX4S and AX4N are very similar, but hydraulically, they are not.

 

[BrooklynBay]

http://www.explorerforum.com/forums/showthread.php?t=171001

 

[gijoecam]

I do not know a lot about automatic transmissions (the last "big frontier" for me, I just can't seem to grasp it through explanation, but everyting else about a car, I know ), but I do know Ford started using "non-syncronized" transmissions in Tauruses in 1995 (transmissions that employ direct gear selection vs. needing to cycle through gears when accelerating). I thought the Explorer had this in the 5 speed, but I could be wrong.

Either way, there appears to be quite a delay when accelerating anyway, when flooriing it from a rolling stop, it can take anywhere from 5-7 seconds until it FINALLY settles on a gear. Also, it has a studder at mid-throttle takeoff and again at 60mph.

Something else catches me as weird, too. The engine dosen't seem to "match" road speed and acceleration. It almost feels like the engine dosen't accelerate at all, but rather just stays between 2.5-3k RPM, no matter road speed.

Guess it goes back in

That would be called a sequential transmission, not a synchronized trans.

Manual transmissions built in the last 25-30 years are synchronized. Motorcycle transmissions are sequential. Automatic transmissions (in my lifetime at least) are neither synchronized, nor sequential.

-Joe

 

[NHale623]

Why don't you take it back to whoever just rebuilt the transmission?

 

[VDub2625]

Yes, if you read the link, syncronous and syncronized are apparently two different things. My fault

I did bring it back for other issues, such as it has a loud vibration under the car at 60-70 and coasting, and 4 wheel drive low got stuck engaged (his response? "Don't use 4 low, it's pretty useless unless you're towing anyway" ). It will be back in tomorrow to diagnose a transfer case leak from the rear driveshaft output, for the noise, and to scan codes.