Solving electronic control problems in today’s automatic transmissions
Special tools are often needed when diagnosing transmission problems and overhauling units.
Shift Pointers: Reassembling GM pumps with cam failure
For the past several years, GM has used a binary positive displacement vane type pump. The compact design allows for it to be utilized in off-axis applications such as the 8L90 transmission and the third generation 6T40 transmission. Figures 1 (above) through 4 display a view of this style pump in the 6T40 applications. The
How to fix GM 8L45/8L90 no-move and no-pressure conditions
By now you may have heard of, or even experienced, a GM 8L45 or 8L90 transmission with a no-move or no-pressure condition. Conditions of no movement or no pressure after repair have plagued this unit since its inception. Here’s what you can do about them. Condition 1: No movement after fast learn or programming If
Searching for the source of an unexpected transmission fluid leak
As the installer was pumping fluid into the transmission from the right side of the vehicle, he was having a difficult time getting it full.
Transmission slipping in fifth gear: An elusive cause of a common problem
Sometimes, finding the cause of a complaint isn’t as straightforward as one would expect; sometimes, these causes can be very elusive.
Stop/start accumulators: What you don’t know can hurt you
It’s no secret that the auto industry is making big moves these days, but while a lot is new, one thing that never changes is that the men and women servicing vehicles need to be learning almost constantly in order to do their jobs safely and effectively. Everybody knows not to touch hot exhaust parts,
Manual transmission sourcebook 2022
While no longer the dominant market force they were in the past, there are still enough manual transmissions out there on the road to make up a decent amount of work for transmission shops in certain specialized segments; and still, of course, the need for parts for, and the ability to work on, those manuals.
From one problem to the next: When a simple solution becomes complicated
A 2007 Chevrolet Express 3500 comes to our shop with a concern of no reverse and very little forward movement. A quick check of codes reveals the following: P0171 Fuel Trim System Lean B1 Po174 Fuel Trim System Lean B2 P0218 Transmission Fluid Overtemp P0300 Engine Misfire Detected P0455 Evap Leak P0753 1-2 Shift Solenoid
The GM 8L90 Stop/Start or Go/No-Go
The Stop/Start feature many vehicles are equipped with today is in my opinion one of the most annoying features a vehicle could ever have. Of course, my opinion doesn’t reflect the opinion of others, but what is undeniably annoying is when the stop/start feature is not working correctly, especially when it is self-inflicted. Take, for
How to get started with OE ECU reprogramming
The conversation goes like this: I have been paying mobile programmers or remote access programmers (RAPs) far too long. I believe I can save money and time by doing this myself. What type of equipment is needed and what is the cost to get up and running? Let’s find out! In a nutshell, four basic
FCA 62TE missing caged needle bearing
The complaint When the Low Clutch Housing is removed from the Underdrive Center Shaft of a 62TE transmission, one notices that the caged needle bearing located on the shaft between the sealing rings was missing (Figure 1, above). The cause A running change was made in 2010 where this caged needle bearing was eliminated. When
FCA 62TE slipping in second and fifth
The complaint Immediately after overhaul, a 2013 Chrysler Town and Country with a 3.6L engine and a 62TE transmission faults to limp mode. The scan tool reveals trouble codes P0732 “Second Gear Ratio Error,” P0735 “Fifth Gear Ratio Error,” P0792 “Compounder Speed Error,” and P1790 “Fault After Shift” are set. During the overhaul procedure, the
