Hello, here is my issue;
I have a logitech g920 steering wheel playing on PC, it work normaly on all my game but, when i open forza the wheel start shaking and turn left by his own and when i close the game it still do it until i unplug it. There is something coming in conflict with my steering because i try it on a friend PC and it doesn’t do it at all.
I hope someone would be able to find what is my issue, because for now i have a wheel and can only play with a controller 
there is nobody that have the same issue as me?
I havent had this issue on XB1 but I havent tried the wheel on PC.
-k
Mine can pull all the way to the left when I stop the game. But only if I move the wheel a little past center. It then goes all the way to the hard left and stays there. No shaking. I basically fixed it by plugging into one of those external USB hubs that has a off switch. Turn it off and the FFB to the wheel turns off. Turn on and it recalibrates and is on center again. I’m not sure if this is the game alone. I had the same problem before. You might try plugging it into different USB ports. As some of mine only seem to half as work. And it’s a brand new MB?
Do you have the Logitech software installed? Mine did that when I first got the wheel and plugged it straight into the pc to test it. Whenever I went into a menu during a race the wheel would go crazy.
Then I installed the Logitech driver and management software, stopped doing it straight away.
I have the same problem with the wheel only on this game. The shaking and the wheel wants to keep turning to the left. I am playing with the most recent drivers as well.
Wheel Pulls Left Bug:
Are you using a USB2.0 Port?
When I first downloaded Fm7 my G920 felt great, it was very realistic, when the October 10 patch came down it ruined everything, my graphics, wheel settings, everything. I got the graphics set up again but the wheel was garbage, I kept checking the wheel updates and there was nothing new. In the end I thought I’d download the full Logitech software from their website again, that did it everything is good again even the braking is better.
I hope this works for you.
I also had the same issue with the wheel not working on PC, but worked without any problems on Xbox one. The wheel works fine for other games on my PC. Was unable to stop the wheel from vibrating by adjusting settings in the wheel configurator.
Mine works fine on PC and is fantastic with FM7.
I can add that my g920 wheel on pc starts vibrating crazy sometimes and i have to plug it out/in again. Using xbox controller untill the issues are fixed. Usually start after a minor lag in-game. Using a i5 4670k @ 4,4ghz with 16gb ram and gtx1070.
I know I’m in the forza 7 forum because even navigating the forum is hard but we have the exact same issue with this wheel with forza horizon3 on win 10 with an asus card. The screen freezes the wheel cuts out and shakes or shudders until you re-start the game - even though the game is still on screen. Can’t figure out if the wheel cuts out and freezes the game momentarily or the game kicks out the wheel. It happens frequently enough to ruin racing. Have looked at different usb’s, have LGS software, have looked at FFB settings etc - help
Yeah I get that on mine sometimes when I get a stutter, sometimes the wheel is almost like disconnected, have to unplug and plug in again. I thought it was my gtx 960 that was the problem, but it looks like it’s not.
With the gtx1070 can you run everything on Ultra?