1993 Accord Auto Transmission 200k miles

Hard to describe the issue but here we go... Whenever I'm driving, especially around 45-50MPH and going steady or on cruise, the car seems to shake/wobble/shimmy but not to side to side but front to
back. It almost feels like the transmission cannot figure out what gear it wants to be in.. Speeding up or down doesn't make a difference. I can only notice it while going at a steady speed, slowing down or speeding up, it's not noticeable. It "wobbles" the car and it's just super annoying. Any help would be greatly appreciated.
Just a couple notes:
1) Just did a transmission change with Honda fluid and no change. 2) Not a tire issue. Been balanced, rotated etc. 3) Checked all motor mounts. Replaced front engine. All others look fine but I'm not 100% sure on the rear one (big honking one with valve thing) it looks good, but I may be wrong.
Thanks!
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I'm suspicious of the rear engine mount, the big one with the valve (actually a vacuum motor). It is meant to soften when idling in gear and firm up under all other conditions. A quick test: you will see the vacuum hose to that mount goes to a control valve mounted nearly dead center on the firewall near the top of the engine. With somebody holding the brake and idling in gear with the A/C on, remove the hose at the control valve where it goes to the engine mount and cover the fitting on the valve where you removed the hose. The car should shake a lot, demonstrating the engine mount is firming up when vacuum is removed. If it passes that test, leave the hose off and the port plugged, then see if the symptoms are still present. If the symptoms are gone the problem is in the control valve or in the electrical signal (DC) that controls the valve.
The vacuum control part of that valve gets stiff too easily. You can try spraying it with silicone lubricant and exercising it with your fingertip, but it isn't easy to reach and the chance of success is not great. Considering the price of the valve (about $150 US IIRC) and the inaccessibility grasping at straws seems reasonable to me :-)
Mike
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Mike,
Thanks for the reply. I will try that and post back.
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Well, I tried what you mentioned Mike and the engine made no shaking difference with or without the valve connected. So I'm assuming its control valve or electrical signal? Any suggestions would be greatly appreciated.
Thanks for all your help so far.
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