Hey ya'll Need to know where I can find what the stall speed should be for my 89 f150 XLT Lariat 2wd 5.0 AOD Trans. and is it safe to do a stall speed test on this truck? I think it is, but just wanted a outside opinion. thanks

 

Stall speed should be about 800rpm

 

Alrighty thank you. Couldn't find that anywhere

 

Yeah I can't say I have seen it posted anywhere but from having an AOD truck for a long time and doing a lot of stuff with the motor I know the stall speed is really low. For example if the idle speed is raised even a little bit from stock the truck wants to take off and it bangs into drive, I guess if you stomp on the brake and give it gas you might see 900-1000rpm but that's about it.

 

that will work. I have a weird issue and I believe after testing everything on my motor and doing a full tune up, that my torque converter may be the culprit. when driving it lugs horribly at low speeds and rpms, now if I am going near 55 mph and have trans in D not OD it will keep revs up and not lug. going to hook up tach today and see if during lugging if they bounce or not, also going to do a stall speed test.

 

Aj, the AOD has a .67:1 overdrive gear, and if you have 3:55 rear gears it will lug at 55mph.

 

it does it all the time at any speed and any gear, that is low speed and low revs. it just started doing this a week ago.

 

When the AOD is in 3rd and 4th gears, it bypasses the torque converter, direct link into the transmission(center input shaft of AOD). So lugging in 3rd and 4th cannot be a torque converter. Suggest pulling codes and seeing what the ECU is saying is wrong.

I know as my friend snapped the AOD center input shaft in his F150 and he had no 3rd and 4th! Serves him right for a 200hp funny gas shot.....LOL.

I recall the stall speed is 1600 to 1800 RPM on my 89 F250. Do a stall test of no more than 10 seconds max! Heat will kill the tranny from a stall test.

 

Truck never has kicked any codes, I have checked them repeatedly both KOEO and KOER, and continuous. no such luck with any codes. ive done stall speed tests before but normally on high horsepower muscle cars and I know the ten second rule. My truck was used to pull camper before I owned it. Ran amazing for two years and now this. Total loss of power, and lugging everywhere except when RPM's are high. I.E D or kicked down into "passing gear"

 

How the fluid? Is it good and red or is it muddy? When was the last time a GOOD tune up was done on the engine. I think you have a engine condition not a transmission condition. Try dropping the y-pipe of the manifolds and drive it around the block. If the problem goes away it's the cats, it still exists check the egr for malfunction. It can cause the same issue if it's sticking open.

 

Once again everything I the motor has been gone through. Found out last night that the torque converter is going ad trans fluid is dark almost brown. Full tune up done on motor when problem arose.

 

The AOD is very sensitive to the TV cable setting, has that been changed recently by you or a service center? If the preload setting on the cable is too high the transmission will hold gears too long on both upshift and downshifts making the motor lug down before it drops a gear as you come to a stop for example. If the preload setting is too low it will upshift too early while accelerating which makes the engine lug more and reduces performance, downshifts are usually fine in this case. There is a sweet spot in this adjustment for each vehicle and there is no danger in experimenting with it by moving the adjuster 1 notch at a time, just be aware the cable is spring loaded and will snap to 0 preload when the lock mechanism is released so you need to mark the current position and/or grasp the cable so that is doesn't move more than desired when the lock is released.

 

Eddie.. it's my understanding that the AOD achieves direct drive in 3rd and 4th with the body of the TC, the center input shaft is splined to the internal fan of the TC and drives 1st and 2nd gear. I can't explain why your friend lost 3rd and 4th gears after snapping the center shaft but if the body of the TC was used for 1th and 2nd there would be no TC slippage in those gears and the motor wouldn't idle in drive.. so that's definitely not the case.

You have an AOD in an F250? Is it original or something that was swapped in? Again it's my understanding the AOD was not used in anything bigger than an F150.. but we all know there are always exceptions to the rule with these trucks so I won't say it's not possible. It would be more likely that your F250 has the E4OD though.. does it have an OD off switch on the dash or shift lever?

 

When I got the 89 F250 it had a blown 351/E4OD setup(sold the E4OD and got my money back ,just got it for the cab at that time). Got a good deal on a 87 F150 302/AOD and as my 84 F250 cab rotted off I needed a truck, so I installed the 302/AOD into the 89. Drove it about 5 years till few months ago when the 302 ate up the cam sprocket(wore out engine). I have a rebuilt 92 F150 300/E4OD and put that in with the AOD. The E4OD from the 92 does not have a speedo gear on the tail shaft to drive the 89 speedo so I keeped the AOD.

That TV adjustment is very touchy!! I finely got a gauge hooked to the TV port and adjusted it to the gauge 33PSI with that spacer. After that adjustment, the AOD shifts properly and also gotten rid of that drive line clash sometimes going into OD.

Some books say there's a 70%(lockup)/30% slip in 3rd and 100% lockup in OD. A few tranny guys told me its 100% lockup in 3rd and 4th.

As for my observations with the AOD, it does act like a 100% lock up in 3rd and 4th. Hopefully soon I will get a junk AOD torque converter and I'm going to cut it apart to see how the power flow goes through it!!!

 

Did full flush and fluid change as well as filter change on trans no change in how it acts. Tricks not throwing any codes. Fluid was VERY dark and dirty