The non lock up converters in automatics were standard prior to about 1978.

Since then all the converters lockup. This means they have a mechanical connection so there is no lost energy. It is a fuel efficiency thing.

They are a good thing but if you have a lot of power and hit it hard while the transmission is locked up it puts a lot of strain on it and it will break.

 

So for just everyday driving which is best? Thanks

 

So for just everyday driving which is best? Thanks

Lockup converter is best for daily driving. Many performance converter companies sell a non-lockup version for the AOD. It's intended for very hi-performance engines.

 

The way I understand it, the only reason to use a non lockup aod is if the input shafts are not strong enough for your engines output. The non lockup replaces the two piece input (one inside the other) with a single solid input, while stronger, it is less efficient(sp?) due to torque convertor slippage, and generates more heat in the transmission.

Feel free to correct me, I'm always willing to learn more!

 

A "rule of thumb" is that lock-up is supposedly worth up to 2mpg on the highway versus a non locking tranny. Everybody's actaul results vary.
1978? Err, no. I'm not a walking encyclopedia, but I know a little.
The C3, C4, FMX, and C6 automatics were never lock-ups.
C3 transmissions were used up until 1986. They began to be supplanted by the overdrive and lockup A4LD's beginning with 1985 Ranger 2.3 pickups.
C4 transmissions were used up until 1981. In 1981 the C5 was introduced and was used up to 1986. The C5 was a redesigned C4 that had lock up capability in third gear. THis involved a totally different valve body assembly from the C4 and a unique torque converter but a C5 actually shares a LOT of parts with a C4. A C5 generally doesn't fare well in performance use though and never gained much popularity.
The "mechanically controlled" AOD first appeared in 1980. A true overdrive with high gear lockup. Use continued until 1994 when it was replaced by the "electronically controlled AOD", the AODE. In 1995 it was redesigned again as the 4R70W.
The last year the FMX saw use was 1981.
The C6 hung in the longest. The last C6 was to be found in 1996 F350 5.8 trucks. It's replacement, the electronically controlled lockup overdrive E40D was introduced in 1989 and gradually replaced all C6 usage.
"Lockup" is not only for overdrive. Many modern transmissions have lockup capability in third and even second. Not to mention the newer five and six speed automatics. All in the pursuit of an extra MPG or two. No bad thing there, but it sure can make them complicated and expensive buggers to rebuild.

 

1978? Err, no. I'm not a walking encyclopedia, but I know a little.
The C3, C4, FMX, and C6 automatics were never lock-ups.

The first lock-up converter was in the 1949 Packard.

They became popular in the late 70's.

I never said Ford was ahead of the game.

 

1949 Packards became popular in the '70's? Gosh.
No, just poking at you. I tend to think in Ford terms, especially when posting on a Mustang forum. What I was getting at was that "...prior to 1978. Since then all converters lockup." Is erroneous by showing that many (Ford) transmissions continued in production well in to the 1990's without the benefit of lock up converters. I do not in fact know what Packard, GM, Mopar, etc did. Basically because none of those marques interest me and I've not looked into them. I did learn something today about Packards though, thank you.