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Reading the blogs here I keep seeing that that the Ultramatic in High range should have a torque converter lock in at a highway speed. I don't know if mine is doing this or not. I thought I felt it change when driving around 55 or 60, but only the one time. Now it seems to stay the same. If I plug in a tach what should I see in RPM difference if the Ultramtic does lock in to the torque converter? My Ultramatic is not a gear start.

You're not supposed to feel it. I think in normal driving the torque converter locks up around 20 MPH.

My 1st generation Ultramatic (under light acceleration) switches to direct drive around 22-25 MPH.

Don't remember anyone mentioning a specific RPM drop but several have mentioned they can hear a slight sound change as the engine slows when DD engages. If you put a tach on & see a reasonable drop off it is most likely going into direct. If it stays at the lower RPM at steady speed and you can make it kickdown (if you're below 50 mph) I think you could be comfortable the direct is coming and staying in.

Willis, HH provides a good description of what you should feel and the only thing I can add is that depending on the type of transmission fluid you are using, the converter lock-up can certainly feel different. I was concerned with my converter locking up and couldn't determine positive engagement with the Dexron II that the previous owner was using so I decided to drain it and refill with Ford "Type F" fluid and it made a considerable difference in the "feel" of the lock-up. After changing fluid I immediately began to feel both the lock-up and the drop off in RPM's which if I recall correctly was a fairly low number like 200 to 400 RPM's.

Thanks for all the info, I can check it out now and see if I can tell.

Quote:

Try it from a dead start and ease into the gas pedal...the slower you reach the point of engagement, like roughly 15+/-MPH, the more defined the lock-up should feel and be heard.

Gator gives a good method and is right that the lockup is more noticeable at low speed under light throttle, though if the trans is unmodified the lockup under the lightest of throttle should come about 22-25 mph. Another thing you might be able to sense when driving is that after lockup, you should have the sensation of engine compression braking as you slow down from speed, exactly as you'd have in a standard shift car in high gear. And along the same lines, if lockup is occurring and you accelerate lightly at low speeds you might detect some engine "lugging" exactly as you would in a standard shift car in high gear when accelerating from a low speed. Yet another simple observataion is that when you give throttle to accelerate (but not enough to kickdown back into converter), if you feel or hear the engine reving up over the rpm you had just previously, either you didn't have lockup, or the trans wasn't capable of holding into DD, or the throttle pressure adjustment is considerably out of adjustment. Doing this last test with a tachometer on the seat next to you should be very definitive.

When in doubt, start with an adjustment of the throttle pressure, just follow the shop manual for that.

Hey Willis:

Lock out quality varies in the Ultramatic but if Direct Drive is not engaging the fluid should be overheating as well. Thus, verify fluid level and condition before testing. If it is burnt smelling there is a problem.

The best way to verify lock up is with gauges. If you take the appropriate pages out of the manual and go to a trans shop they can hook up a gauge and check the Direct Drive line pressure.

The lugging suggestion is good as is the light throttle check. Direct should be engaged by 56 mph regardless of throttle, and if the car labors above this speed the pressures should be checked.