R&R Tech
- Subject: Additional work required during or after transmission installation
- Unit: AW55-50SN; 09A, 09G
- Vehicle Applications: 2001 Volvo V70 XC AWD; VW
- Essential Reading: Rebuilder, Shop Owner, Center Manager, Diagnostician, R&R
- Author: Jody Carnahan
In last month’s issue, fellow technician Jim Stokes provided some insight on problems that can occur during, and after, installation of a repaired transmission. This article focuses on some installation issues that you probably should be aware of prior to making the sale of the transmission. This involves additional work that may need to be done after the transmission has been repaired and may require subletting a portion of the job to another shop, or even taking it to the OE dealer.
As most people in our industry already know, the vehicles that are visiting our shops today are very complex and equipped with various computer controls that require use of multiple control units for each specific system within the vehicle. Prior to quoting or making a sale on an overhaul or a remanufactured unit, the shop owner and/or service writer needs to know what additional work may be required to get the job completed.
A full understanding of the vehicle’s requirements for the repair must be considered. Most of the vehicles we are working on today will require some type of relearn or reset procedure after the transmission has been repaired or replaced. In addition, some vehicles will require PCM or TCM reprogramming before any relearn or resets can be performed. This can be true even when you’re doing a minor repair that does not involve removing the transmission from the vehicle, such as replacing a valve body, solenoid etc.
I know that relearns and resets are not new to most shops, and some shops already have equipment to perform reflash and reprogramming operations on most vehicles. Unfortunately, performing relearns and resets on some Asian and European vehicles can be a challenge, as most of these vehicles require a dedicated OE scan tool or software to perform the procedure. Many shops have told me that they have worked on several European vehicles and have never had to perform a relearn or reset after the repair was made. I’m not sure whether they just got lucky or it was because of how the previous unit failed.
Let’s look at an example of what I’ve discussed. Let’s say that you were working on a 2001 Volvo V70 XC AWD, with an AW55-50SN transmission, and the vehicle had been towed in because it suddenly quit moving. You discovered that the transmission had a problem in the final-drive area but you found no other issues. All the clutches were like new, and there was no obvious wear in the valve body etc. That being said, the transmission was probably operating normally just before the final-drive component failed.
In this particular instance, the computer was not trying to adapt and ramp up pressure for a slipping clutch etc. This would likely be one of those instances in which the vehicle might road-test perfectly after repair or replacement, even though an adaptive reset wasn’t performed.
Let’s use the same vehicle in a new example. Now the complaint is that the transmission is slipping in third gear, spins up but is shifting OK. The customer has advised you that it has been functioning in this manner for an extended period. When you disassemble this unit, you find that it has burnt clutches and worn valves in the valve body, and the solenoids don’t function properly.
After you make the repair on this unit, I can just about guarantee that you will not merely be able to test-drive it (without performing shift adapts), then send it down the road. This is an instance in which I usually get the tech call with the common complaints of banging on the 2-3 shift and a harsh downshift clunk when the vehicle is coming to a stop. By now you probably know where I’m going with this, because shift adapts need to be reset and the TCM needs to be put into what Volvo calls “Adaptive Control Mode.” Some early Volvos (2001-02 models) will require software updates to get them into adaptive control mode. The kicker here is that your latest, greatest aftermarket scan tool will not perform this function correctly. That’s right; it’s now time to visit your local dealer for help. All too often, the closest dealer is 100 miles away, and the trip and dealer charges will cost you.
I’m not going to single out Volvo, since most of the other carmakers (whether European or Asian) will require some type of adaptive relearn, or TCM initialization, to make the transmission perform properly. Nissan vehicles require a TCM initialization, and in most instances it can be performed only with the Nissan Consult II or III. This is the same for Volkswagen vehicles, which need the TCM set back to “basic” settings using VAG software, or equivalent, all of which may require you to take it back to the dealer for these services.
One more note on the TCM with regard to Volkswagen: There is a Volkswagen TSB that most shops do not know about. It involves certain models with the 09A and 09G transmissions. A certain percentage of these vehicles will require an updated TCM when the transmission is replaced. For your reference, it is bulletin TT 37-06-06, which says that when replacing one of these transmissions (09A or 09G) you must replace the TCM at the same time. To find out whether the vehicle you are working on is affected, you will need to call your local Volkswagen parts department, give them the complete VIN and have them check to see whether a TCM is needed when the transmission is replaced. This is another expense that you would not want to explain to your customer “after the fact.”
I hope this information has given you some insight on vehicles that likely will require additional work after you perform a transmission repair. As I said earlier, you will need to know exactly what you are up against before quoting a price on one of these jobs.
Jody Carnahan, warranty director for Certified Transmission, has been with the company for more than 25 years.
