1986 spider graduate

[ROBS38@domain.elided]

I get a thumping noise coming from the middle to the rear of my 86 spider 
graduate
It started out only when I took off in first but now is also appearing in 2 & 
3 gears
when I am in 5th cuising on the highway it doesn't seem to be there
Does anyone have an idea what this might be? My mechanic said the cross 
member located under the tranny was bent and changed it but it didn't help

Bob Schwartz
NY
1986 Spider Graduate                                                

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