March 2007 Archives - Transmission Digest
Revisiting the Captive Clutch

Joe Rivera proved that the ZF 5HP19/24 converter with captive clutch is rebuildable (see “Rebuilding the Unrebuildable,” Transmission Digest, December 2005). Many converter shops are now trying to build this unit, and the number of rebuilding questions continues to increase. A recent rise in issues related to lockup performance after rebuild has prompted a closer look at this unit. The same fear factor that prevented many shops from trying to rebuild this unit in the first place is now causing some of the braver rebuilders to have second thoughts.

‘I Don’t Work on Imports’

The other day I had an interesting conversation with Bob Augustine from Vetronix Corp. in which he reminded me of the day when good old carburetors were being replaced with fuel injection. And you would hear technicians say, “I’m only a carburetor guy; I’m not going to work on any car with fuel injectors.” This made me think of how often I hear transmission technicians say they will never work on imports. The term “import” is becoming increasingly difficult to define.

Pilot Error

It turned out that about 90% of accidents resulted from pilot error. Even some of the weather-related crashes could have been avoided if the pilots had followed proper procedure in checking the weather beforehand or not taking off when the weather was too bad. There were even incidents in which planes ran out of fuel because pilots, who did not anticipate weather problems, thought they had enough to get where they were going.

Making Money off the ‘Daily Grind’

No, I’m not talking about our daily routine, but rather a routine we perform daily that not only makes our shop money but also saves valuable time. I’m talking specifically about the salvage and reuse of parts that otherwise would be scrapped, using a piece of equipment many shops already own but may not be using to its fullest potential.

Repairing the New Venture 261 & 263 Transfer Cases

For the 1999 model year, GM introduced the new Chevrolet Silverado and GMC Sierra models of pickup trucks. As part of the upgrade of these models, New Venture Gear designed a new series of transfer cases, the NV 261 and 263. These transfer cases are basically a heavier-duty version of the NV 241 transfer cases used before 1999.

To 6HP or not to 6HP – Is That a Question?

ZF Friedrichshafen (meaning Zahnradfabrik Friedrichshafen) is a leading supplier of automobile transmissions. The company was founded in 1915 in Friedrichshafen, Germany, to produce gears for zeppelins and other airships but moved into the automobile market by 1918. The company helped produce the airship Hindenburg as well as truck parts for Hitler’s war effort. ZF is also known for designing and manufacturing the transmissions for most German Panzers of Word War II.

March 2007 Issue

Issue Summary:

After replacement of either the transaxle or the TCM, the transmission exhibits either a neutral condition after reaching 6 mph or a harsh 2-1 coast down-shift.

After transaxle replacement, the vehicle may exhibit erratic shifts or diagnostic trouble codes related to gear-ratio errors.