Hey everybody

I have a 1993 with the AOD transmission. I've been having problems with a bad shudder once the torque converter locks up. After I hit about 40 mph the whole thing starts shaking and it is impossible to accelerate. If you shift out of o/d you still can't get on the throttle too hard or it will shake real bad. As long as you ease the throttle, it works ok but even pulling out it seems like the t/c is locked in first second and third. It must unlock as I slow down though, because the truck doesn't stall out. It feels to me like when the shudder starts, the converter is between lock and unlock like in and out? I don't know but I just changed to Mercon V on Friday. Anyone who knows a lot more than me know what this could be??

Thank you for your help!
Matt

 

well do you have an aod transmission or an aod/e(4r70w).
The aod was direct drive in 3rd and 4th the 4r70w has a lockup clutch and lockup solenoid which could be sticking. Either way it sounds like you have an ignition problem.
Alan

 

Thanks Alan,
I have the AOD for sure. The shifter has OD,D,1 on the column. So its ignition?

 

Anyone else want to put in their two cents?

I'd appreciate anything!

 

When was the last time you changed plugs and wires? If it's been a while (80k miles), I recommend you change plugs and wires. You may also consider buying a can of Seafoam and run 1/3 can through the brake booster line and put the rest in the gas tank. It will help clean the intake and cylinders; you will probably want to change the oil soon after the treatment, though.

Make sure you get the plug wires back in place in the proper order and watch the distributor rotation for clockwise/ counterclockwise rotation. Some folks rip all the wires off, put the new ones on and then find out about dist. rotation.

Hope this helps and keep us posted.

 

Thank you Cliles55.
The plugs were just changed about 10,000 ago but not the wires. I have 99,000 on it now and the wires were changed by the previous owner but I don't know when. If I give the seafoam a try, I'll let you know what happens. It might not be until next weekend though.

 

Could it be a K&N airfilter that made this more noticeable? I just put a universal cone filter on and that is around when this became worse than it was before that.

 

Also could it be the O2 sensor??

 

My philosophy: do the simple and inexpensive first. If something starts to run wrong, go back to what you did last. I've found my problems are solved in that order.

Knock on wood, I've not had catastrophic failures of anything in my life; heck - I flew on Navy P-3s for 9 years and racked up 3,600 flight hours and only had maybe 3 emergency shutdowns. Maintenance on the road was fixed in the order I mentioned. I believe in the Air Force principle of things: KISS (keep it simple, stupid).

Regards,
Curt

 

I like your way of thinking cliles55
Thanks man

 

What kind of Seafoam should I use for this? Choke and carb cleaner and run it through a vacuum line?

 

Anyone else have any suggestions or has this happened to any of you all out there???

 

There is the possibilty that your egr is stuck open as well, have you changed the plugs and wires yet? what about the cap and button. That truck should have a TFI module as well and they are known to have problems.
Alan

 

Thanks dirtydog
I did replace all the plugs but not the wires or cap and rotor. What all should I consider replacing with the distributor? Cap, rotor, wires? The plugs only have about 5K on them.

I am planning to take off the egr and clean or replace it. Also, I want to run seafoam through the brake vacuum line to clean the intake and injectors. Would the seafoam clean the egr without taking it off? Also, if you know of a link to instructions on how to disassemble the egr from throttle body and clean it, that would help. Thanks again