"shudder" in D and R in '91 740 wagon

Hi, I just got a '91 740 wagon about a month ago. It has 167K on it. About two weeks ago I noticed that when I am slowing down to stop it will "shudder" for about 3-5 seconds when stopping at a stop sign or red light and in Drive. Then it evens out and is no problem.Runs smoothly when driving at normal speeds. It has also started doing it some when I shift in Reverse. Mechanic said that a new transmission mount had been installed recently. Just had transmission power flushed yesterday as well as fuel system. Any suggestions? I am getting a 321 code(Regina system) but don't think that is related. Thanks for input. JB

Reply to
JB
Loading thread data ...

Sounds like you need to tune up the engine, the shudder is probably the engine stumbling as the load increases at idle when you stop the car. I don't know what that code means but find out and fix it before you chase your tail.

Reply to
James Sweet

Did they do a thorough flush? What transmission fluid did they use? Usually a shudder on decell just before stop is the lockup converter clutch not releasing smoothly. OTOH a shudder in reverse when backing up could be the front clutch slipping, or something as simple as a bad u- joint.

Bob

Reply to
User

Bob, Interesting that you brought up the transmission fluid. It was an O'Reilly's generic Dexron III. The mechanic used a brand of cleaner,and conditioner that I can't remember. He put the cleaner in before the flush. Flushed it with a machine(machine was same brand as the cleaning agents) and then added a can of conditioner after the flush. The old fluid was very dirty.. My mechanic owns an import shop. He is a Volvo certified mechanic with about

20 years experience. He uses mostly Volvo,Bosch and some other Eur> > Hi,
Reply to
James B.

I've never heard of O'Reilly brand anything except for the guy on the radio. Volvo lists some caveats deep in the literature mumbling about a license number that should be stamped on the bulk drums or somwhere n the case box for quart bottles that authenticates the formulation of the fluid. If the license number exists it's pretty much the same as motor oil meeting the SAE flavor of the year. If the old trans fluid was well spent and there was some wear in the transmission friction parts then the new fluid with a fresh friction modifier package can provoke a different shift feel. I use Dextron III from Pennzoil or Quaker State (same company now) and it indeed does have a license number on the product, for what it's worth, but I seldom have any problems on a car that was shifting fine to begin with.

Bob

Reply to
User

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.