Is my 4L60E in overdrive?

[Lawrence]

Hi Steve, I've already done the shifter as the car had the original horseshoe one on when I got it, and now it's got a Hurst one. It changes all the way up and down and there is no slack at either end of the shifter throw. I counted the shifts as you suggested, and it's only in 3rd at 70MPH. I took it on to 90MPH and it still didnt change up a gear. Guess I should get one of your shrifters to "test" it eh?

[Steve Chryssos]

Guess I should get one of your shrifters to "test" it eh?

No. You would more than likely you would experience the exact same problem.
Anyway, there's no need to get the thing up to 70 or 90 mph. That's not helping. To the contrary, try testing with jackstands under the rear axle and the rear wheels about two inches off the ground. Chock the front wheels. This will remove load from the equation. Shifts will be based entirely on vehicle speed. It will be easier for you to follow data on the laptop under these controlled conditions.

Oops! Don't forget to reapply the brakes before shifting back into park.

[Lawrence]

I replaced both o2 sensors and a maf on the car last week, which made it much better than it was, and I also did a set of new plugs on the weekend and disconnected the battery for half an hour to start from scratch. Yesterday I managed to average 19mpg total driving the 60 miles I cover going to work and back. Will get it on the ramps at the garage across the road from work and get real numbers on RPM and shift points. Thanks for all the advice and suggestions so far, I still think I should convnice myself to get a shrifter.....

[Steve Chryssos]

We'll be here when you're ready.