I just bought a mint 1989 760 gle turbo. All is mint except that the seat back won't recline, therefore no headroom. All the other functions, i.e, forward/backward seat itself work. When I do try the recline seat back switch, I get a thumping on my back when switching forward, and thumping to the rear of the seat back trying to recline back. Any ideas? Thanx in advanced- Curtis

This will not be much help but mine does the same thing too. I think the connections are good as are yours hence you can feel the seat trying to do something. Try going as far forward as you can then recline . Also try letting off on the lubar support (circular crank on the left of the seat) that helped me once but no longer. I get a click with no response.

What it is, at least on my 90' 765 was that on each side of the seat is a big gear that lowers and raised the seat back what turns this big gear is little worm drive attached to the motor underneath the seat. the groove on the worm gear break and dont turn the big gear. And also because it is made of plastic where it attaches to the motor cable splits and just spins not turning the big gear.
You have to take off the plastic side piece on the seat then the cover and you will see the gear. there is a gear on both sides.

Bernie franklin

I have the same problem with my seat. The plastic geat is split and just spins on the shaft. Does anyone know where I can locate just the plastic gear?

Seems crazy to spend $265 when all I need id the plastic gear.

Good news all. I took it to my local Volvo dealer. They said $690. dollars American would fix the problem. Frozen actuator. I said riiiight. Took it apart myself, fixed it in 5 hours. It seems that some foreign debris got caught in the seat gear. Used a a car battery to drive motor to troubleshoot.

Thanx for the responses. They on the money. Curtis