I own a 1990 740GL. 260,000+ Miles. Engine run quietly when on neutral but when I get mooving it kinda shakes the whole chassy. Specialy when shifting second and third. This is automatic transmission. Car haven't been maintained well last 50,000 Miles but have record till 105,000 by the dealer maintenance.
No leaks, Some noises from engine but nothing serious, T-Belt not been changed on time. So does the Timing adj. & Valve Clearence Svc. Transmission filter never been changed.
Engine doesen't starts right away at cold. Sounds like fuel filter. Retired person used and they didn't sound like that they give a damn about service.
Before I touch my savings, I would like to get some insights. A very honest service specialist said that there may be not be any problem in the car at all. I'm not affraid to get my hands dirty, but leaving big work to the shop. please let me know where to start. I want to get this back to normal maintenance level.

I would look at motor mounts. This sounds a little like my '90 745 GL(68 K) and new mounts fixed it right up. Not too bad a job to install.
Dane Klaproth('90 745GL, '78 BMW R100SRS)

Thank You SooooMuch, never thought of that.

Especially the rear transmission mount. Sounds like it's no longer got any rubber intact. The big front ones are hydraulic and at this age they're probably bad, but they usually cause engine shakes at idle, as opposed to while underway.
I'd also check plugs, cap and rotor- you could be having a misfire condition causing rough running.
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Rob Bareiss, New London CT ::: '87 244DL/M47- 221K, 88 744GLE- 202K, 91 244 181K, 88 244GL 145K

Check the motormounts, and replace if necessary.
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Kenric Tam
1990 Volvo 740 base sedan (B230F)
My Volvo 'Project'