VickMacky

So I remembered about this while driving today and thought I'd see what happens if I turn on the hazards while in OD. I was cruising at 50mph right at 1500rpms (94 5.8 E4OD) and as soon as I turned them on I seen the RPMs raise about 150-200 RPMs. Once I turned them off it went back down to 1500. I couldn't feel anything like a down shift but I assume it was the converter unlocking. I also didn't leave them on as I didn't to cause damage but to me it seems this thread is true. I don't have the knowledge in electrical wiring to discuss how it works but it seems it does.

jtetterton

I've got a 94 Bronco 5.8 with e40d and mine does the same thing when turning on the hazards while driving.

VickMacky

So I guess as long as you're driving <30 mph you should be OK since the converter isn't locked until 34 mph.

mustangGT90210

It's converter locking and unlocking. These trucks are wired up in a way that when the brake lights come on, the converter unlocks.

I had TPS issues causing my converter to be all weird, so I got looking through the workshop manual. The converter unlocks when you let off the gas, and when the brake lights come on. Went my TPS went out, it was telling the computer I never let my foot off the gas, which was causing the converter to stay locked down to like 28 mph, had to tap the brakes so it would unlock and downshift.

The converter doesn't lock up until somewhere around 35mph on my truck. Basically, you shouldn't be driving fast with the flashers on anyway, so I think that's where they got the idea for the programming.

But yes, if you're going down the road at 40+ and put the flashers on, it can definitely kill that converter locking it and unlocking it every time they flash. Don't do it!

James Hampton

was this resolved? lol
thanks for all the info