More Torque-Converter Forensics
Try to imagine the difficult job tech-line technicians have. They are asked to decipher bits and pieces of information that may not be accurate and then come up with the correct answer. The information the technicians collected for the following two scenarios seemed to be as different as night and day. The information even originated in different countries. The amazing thing about these different complaints and symptoms was that they all had the same root cause.
Shop Owners Are in the Driver’s Seat
It wasn’t very long ago that finding employees, especially technically skilled ones, was somewhere between difficult and impossible. If you ran an ad hardly anyone called other than possibly some misfits who were truly unemployable because of any one or a combination of the following…
February 2010 Issue
Issue Summary:
A Dodge/Chrysler/Jeep vehicle with a 45RFE transmission may exhibit a harsh torque-converter clutch application, or the engine may stall or stumble on a garage shift into Reverse or Drive (below).
Some Daimler/Chrysler vehicles equipped with the NAG1, 42RLE or CVT have no transmission dipstick for checking oil level (page 3).
After overhaul, a Dodge/Chrysler/Jeep vehicle with a 45RFE transmission may exhibit a complaint of no movement (page 4).
A 2003 Jeep Liberty with a 3.7-liter engine and 42RLE transmission developed an engine vibration after engine replacement (page 6).
Advanced Diagnostics: Thinking ‘Outside the Box’
As automotive technology and design have reached new levels of sophistication, the role of the diagnostician has risen to critical levels. It is possible to replace transmissions and transfer cases with factory or aftermarket new or remanufactured units with relative ease. The shop needs only a qualified installer to make the swap.
It’s not just the Transmission
Recently a customer called to get a quote for a 1998 Ford F-150 4X4 with the 4.6-liter V-8 engine and 4R70W transmission. The price was given and we had one in stock. A couple of days later they called and told us they needed the transmission. It was still in stock, but it was late in the day so we made arrangements to deliver it to them the next day.
Finding the cause of Honda 740 codes
Many converter shops have reported having Honda converters returned to their shops because of 740 codes. In most instances, the remedy was to install a new OEM converter.
Allison 1000/2000: TCC Cycling or Surge
In ATSG’s “Shifting Great in 2008” technical-training seminar we covered a complaint of TCC shuttle or surge with GM’s medium-duty trucks using Allison 1000/2000-series transmissions. This complaint usually occurs after converter replacement.
Never too Late to Fix It
The simple answer, of course, is to adjust the amount of business you do to the expenses. When you are pretty far behind in paying your commitments it’s either because the business costs too much to operate or it doesn’t make enough sales – or shall we say enough profitable sales – to generate the proper revenue. More often than not it’s a combination of the two. Expenses have quietly grown over time and business has withered.
GM’s 2ML70 Hybrid Two-Mode Transmission
GM’s 2ML70 hybrid transmission (Figure 1) is a four-speed unit with fourth gear being overdrive. Applications include the 2008 Chevrolet Tahoe and GMC Yukon and the 6.0-liter 2009 Cadillac Escalade. It also was used for a short time in the 2009 5.7-liter Chrysler Aspen and Dodge Durango. BMW uses the two-mode 2ML70 in its ActiveHybrid X6, and Mercedes-Benz also uses it.
Getting Down to Business
I have been in this business a long time, and I still relish the feeling when I find the fault and fix the car. The root cause is the critter I’m always on the prowl for, and I will use any weapon I can find to bag that beast. That often means extra hours and every resource in my shop; however, I have been fortunate lately to catch some interesting issues fairly quickly by using the correct tool. Following are some situations I’ve encountered recently. Which tool would you use to correct them?
Tough Times Bring Out Creative Types
Tough economic times bring with them differing circumstances for different industries. For those of us in the independent automotive-service field, we may be seeing more and more repairs being attempted by less- and less-qualified technicians. It seems like there is an endless supply of advice to help automotive-service “newbies” figure out their car’s technical woes, thereby saving them the time and trouble of taking a car to a “professional.”
Lubrication
One of the things often neglected is lubrication of the transmission, transfer case and differential. As with the automatic transmissions there are now dozens of specified lubricants that a professional shop must have available. What used to work no longer does, and putting the wrong lube into a late-model unit will result in spoiling a good rebuild. You must use the correct fluid for the unit you are working on. It sounds logical, but if you understand why, it will go a long way toward preventing shift complaints and outright failure under warranty due to incorrect lube fill.
