4r70w swap help
 

Cannot get 4r70w off a 4.6 to mate up correctly on a 5.4. Tc seated properly before I started. Almost 100 percent sure it engaged into pump. Had to use bolts to mate together, found out later that's not a good idea. The closer the tranny gets to mate with engine the harder it is to turn crank. I had all bolts in and tight before I knew it had locked up the motor. What am I missing, do I need to swap flex plates? 4r70w is an 03 that's original to the truck, I swapped engines with a 97 5.4

should be 1/8 clearance between converter and flex plate when tranny is bolted up to block......if not you do not have the converter seated all the way! Remove/loosen bellhousing bolts and remove converter bolts. Slide tranny back and get rotate/seat converter. Hopefully you didn't break off the drive pump ears..
Flex plates are the same 4.6-5.4 CONVERTER is different from 5-4 to 4.6 ...different stall and torque multiplication ratio. If the converter bolt pattern fits the flexplate pattern...yes it should work.
BTW engaging the converter can be a real PITA sometimes....when I rebuilt mine....as i tried to install it (heavy sob too...) i completely removed from under the truck and tore into the front pump to make damm sure i installed the drive collar CORRECT...and ..YES i did...just didn't get the converter to FULLY seat.....3 1/2 hrs later....back to where i started putting the tranny back in the truck.... PITA

Might search for measurement from tranny bellhousing face to converter face when fully seated.....i'm sure there is a NUMBER out there

Thank you. I'm going to measure those two points. Also a weird thing I noticed is the converter is closer to bell housing at 12 o'clock. I thought output shaft was bent at first. But as I rotate the Tc the distance was consistent as it rotated. If that makes sense. That made we wonder if it was designed that way because if shaft was bent or the converter then it should have kept that difference in spacing at the same point on the converter as I rotated but instead each stud in Tc was closer to bellhousing at 12o'clock.

Do you have the bellhousing spacer plate installed?

Something that might matter - the transmission was on a 03 4.6, but the 97 5.4 had a E4OD behind it.

Yes

Well luckily I have both engines and trannys sitting here to compair. I've put the 4r70w Tc in the e40d and vise versa, I checked everything before I took it under truck. Well except a good measurement. I did measure Tc on e40d and it was around 7/8 from tc to face of bell housing. The bottom of 4r70w is 7/8 but that 12 o'clock position it's much more shallow, like 11/16 or so. The bell housing on e40d is consistent all the way around. It's like the 4r70w bell housing isnt level with output shaft, like they designed it to point downward a bit as it mates to engine. Although I haven't had time yet to make damn sure my Tc is seated properly on the 4r70w this is my findings and I'm stumped. May have to do more digging to find a reason for this difference in trannys and how it affects the attachment

converter face and bellhousing MUST be parallel no 2 ways around that.....

Ya that's my thinking too. After looking at it more there is enough play in the Tc shaft to make it not parallel unless I hold it up myself. I've tried 3 times now and no change. My next attempt is to hold Tc parallel like your saying maybe with some sort of wedge in the inspection hole.

They aren't that expensive - possibly a new TC and/or flexplate may take care of the problem.