any help i am going nuts

[93punow]

hi guys my problems all started after i changed the heds on by 93 6.5 td. the trans will only shift into thrid no overdrive it shtfs at 3000 rpm when i first drive it after that it shifts ok. i have replaced tcm,shift sol. input and output sensors. i have also repalced ops coolant senor. my oil pressure running at about 30 running down the road at idle falls to o. egnine sounds ok i can't figure this out any help please!!!!!!!!!!!

[rhsub]

First of all
what trans 4L60 or 4L80
what truck model
which engine vin s or f
If this all happened after the head replacement I would first check all my electrical connections and grounds, make sure you have not missed the ground at the rear of passenger side head, visually check all connectors for damaged or backed out terminals
Good luck
Ron
PS would be a lot easier to read if you spell checked

[ttpost]

i would check the oil pressure with a mechanical gauge, just for safetys sake and make sure your grounds are good on the right rear or the passenger side of the intake manifold. if i remember right there are 3 ground wires that bolt up there. make sure you didnt damage the wire loom going to the tranny hope this helps rob

[93punow]

the trans is l480e vin f 2500 two wheel