car shakes at 50 mph

[raygv]

I got a 1993 4 cyl camry. the car is smooth and quiet when accelerating but when I reach cruising speed of 50 and the car drops into overdrive the car shakes and there is a loud humm sound it almost sounds like road noise but if I press on the gas and the car kicks down it feels smooth again. if I got over 50, say 55 the car is smooth again. any help?

thank you
Greg

[toyboyracer]

Balance of front wheels is out OR if you have roof bars they are humming !

My mechanic back in 1983 spent DAYS trying to find why a customers car was hummiing/thrumming after having his front discs machined...

No roof bars when job was done, customer put them on when he got the car home
that evening then all hell broke loose !

Discs were removed & re-machined, new pads, new wheel bearings
ALL FREE of charge by mechanic as he felt it was his fault...

And it was just the bars which ook 5 mins to REMOVE !!!
We laughed about that for YEARS !

[Reppinshadyvill]

Start simple is your tranny fluid where it should be?

[fredk]

balance the tires