Download You can tell a lot about what’s ailing a sick A/T just by looking at the condition of its ATF. It can help you accurately diagnose an A/T problem before you replace solenoids or order a reman A/T. Here’s how you do it: 1. Use a fine-mesh strainer to drain the ATF from the sick A/T and A/T cooler into a clean container. (A disposable paint strainer or coffee filter works great for this.) 2. Look at the condition of the ATF: • If the ATF is very clean and the A/T slips, flares, or shifts harshly, solenoid replacement will usually fix this problem and it’s an inexpensive alternative to replacing the A/T. • If the ATF has lots of metallic particles swirling around in it, don’t bother replacing solenoids because the problem will most likely happen again. A reman A/T is your only option. Make sure you flush the A/T cooler and lines before installing the reman A/T (see S/B 89-022, A/T Cooler Flushing Procedure or refer to the appropriate S/M). If you don’t, any contaminants from the cooler and lines will get inside the A/T and then you’ll be dealing with a comeback. • If you’re not sure if the contamination is normal, try draining the ATF from a healthy A/T through a paint strainer into another container, and comparing the fluids.