Bad Shaking Issue

I have a 2005 Dodge Caravan, 85,560 miles on it, and VERY intermittently,
while driving at highway speeds, I will get a really bad vibration through
the entire vehicle. No set time it lasts, some times long (miles), some
times short (mile). No indicator lights come on, car is not getting hot. Oil
changes have ALWAYS been regularly done with filter change and fuel injector
cleaner.

It happened today on my way to work, for along time. Don't really think it
is my engine, cause this time, when I pressed on the brakes, I felt a strong
vibration through the brake pedal. Not sure where to start looking for what
is wrong. Since it is so intermittent, if I take it to the dealership, they
will just turn around and tell me nothing is wrong (like they always do - 4
different issues I had, I had to take it back 2-3 times each before they
fixed it right.)

It would help if I could tell them where to begin to look, if anyone has a
clue for me. Would it be brakes, (tires are all brand new and balanced),
wheel bearings, tie rods, ball joints, CV joints, suspension?

The only thing that I know is wrong with the car is a very small gasket leak
around the water pump. But if this would the issue, would the car overheat
due to the coolant not being pushed through the car?

Thanks for any help,

-Tom Rogers

 

Also, could it be the transmission?


Sometimes (not always) I hear clunks when putting car into gear –
transmission has

been serviced last at 60k miles and has proper fluid level.



Also, when brakes are wet, and I park car for the night, next day I try to

get going and you can hear the brakes rubbing on the discs/drums.

-Tom

 

Who did the trans service and what did they put in? It sounds like torque
converter shudder. Typical of what happens if someone puts in wrong fluid or
additives.

 

Local Dodge Dealer - would this torque converter be an intermittent issue
like I have been seeing?

-Tom

 

2wheel drive or a.w.d.???

 

2 wheel

 

heres a long shot maybe the brake caliper is seizing up intermittenly and you
are felling the warped rotors

 

well, if you actually feel it through the brake pedal itself then it must
surely be due to warped brake rotors or drums.

that said, perhaps some more details of exactly what happens and under
exactly what circumstances might help confirm the diagnosis.

i know i had intermittent "body" vibrations for several YEARS on one vehicle
before I finally found that my tires were the problem. the problem went away
with Goodyear tires having persisted through two sets of Continentals.
Specifically my vehicle, a full size camper van, was right at the load limit
of the Contis and I ran them at max PSI and apparently under certain
variables of load/speed/distance/temperature one or two of them would bulge
or go out of round causing a "shimmy" but totally invisible in the shop. no
amount of rotating/balancing touched the problem.

not saying this is your issue but thought it may be interesting or useful to
the group.