Shutter at RPM

[alexgalexg]

98 XJ 4.0 4wd lifted 3.5"

Hi all,

Recently swapped out my very high mileage 4.0 for a lower mileage one since the machine shops wanted 6k to rebuild mine. The engine runs great, someone was changing the oil every 2k it's a gem.

Have driven it my 30 min each way commute for 2 weeks now and noticed today overtaking someone on a steep grade that at 3k I get a pretty good vibration from the bell housing area.

For context, the donor 4.0 came from a manual 98 tj. So I used my known good flex plate. When I connected the plate to the torque converter I marked the 1st bolt I installed, lightly screwed in and rotated the engine by hand tightening them more and more over 4 passes. Only resistance I got was from engine compression.

I'm a little stumped at where to start with this. Direct corelation between the shaking and high rpm and just curious if you all have any thoughts.

 

[Ecomike]

Torque converter unlocking, and relocking, or in the wrong gear for the steep grade?
AW4 or manual trans?

 

[alexgalexg]

Torque converter unlocking, and relocking, or in the wrong gear for the steep grade?
AW4 or manual trans?

I pulled the transmission today. It is the rod on the end of the torque converter. It is slightly bent.

Rock auto lists two different torque converters. Part numbers 783, and TO28. Going off the pictures my torque converter looks like the TO28. Not sure if you or anyone else knows the difference.

 

[THE2NDXJ]

Just outta curiosity, is it the rod that engages at the transmission input? Thats pretty beefy, Im wondering how that happened.

 

[alexgalexg]

Just outta curiosity, is it the rod that engages at the transmission input? Thats pretty beefy, Im wondering how that happened.

Wheel chock moved while I was putting the engine in and the weight of the trans was all on that shaft for a moment. Guessing it happened then.

 

[alexgalexg]

At a loss. Mounted the transmission back up to the engine gently. Tc spun freely enough for me to use a screwdriver to line up the threads with the holes on the flex plate... when you tighten the torque converter bolts the engine gets really stiff...