Ok so here it is.

I finished work on the highboy project sunday night. It fired to life first try, which was a nice change.

I followed the proper procedure to get fluid into the tranny, but no engagement ever occurred once full. Add to that a nasty intermittant noise.

So it goes to Aamco. They had rebuilt the unit for me, and provided a TCS convertor, p/n HD-44. That p/n does check out as correct for the application. Truck was going to Aamco anyhow for a cooler installation and TV adjustment, for warranty purposes.

I must add, that after a little uncertainty on my part, the guys at this particular Aamco have totally come through in a big way, and I'd have no problem referring anyone to the particular shop I'm dealing with. They are being very up front and honest. All I am trying to do is gain information which may help solve the problem.

So they pull it apart, see the front pump is toast, and it looks like it was due to incorrect tourque convertor installation. My bad -so it would seem.

Ok, I'm ready to swallow my pride, and cough up another G.

They get back to me today and ask me what flex plate I'm using, as when they are going to reinstall the unit, they cannot seem to make it happen.. not enough clearance, pressure on the TC, although all bolts line up and starter is happy.

Well, I tell him that through Hollander software I have, that I'm using a flex plate from an 88 F150, 4.9L, with AOD.

I had gotten the Hollander #, called Ralph's, and went down and pulled it myself from an injected 4.9L they had there, out of an '88 with an AOD. (Only other auto behind that engine offered in 88 was a C6.) I check the part, and it seems to be the only AOD flex plate used behind the 300 six since 1983 in any model of truck or van

I am certain that I provided them with the proper flex plate, as in comparison with a known 5.0L AOD flex plate, the only visible difference was the lack of the counterweight the 5.0L uses for balancing.

Well there is my doozy!

..and yes, I am using the proper shield/inspection cover..


I am going to get another flex plate tomorrow just in case I did get the wrong item.

One question I have.. Are the flex plate to tourque converter bolt patterns the same for C4,C5,C6 and AOD??

 

Was it a stick truck before? The pilot bushing may still be in the crank.

 

not the pilot bushing. have discovered that there is a different offset between C6 and AOD flex plates, and the flex plate I have is definitly from a C6.

300 six to AOD flex has a 17/32 offset when measured from crank mount surface to Torque converter pad mount surface, vs 23/32 for C6 and E40D, AODE.

And wouldn't you know the right flex plate is rather hard to find here in Vancouver. Spent all day at it today.