170,000 mile 1999 Grand caravan LE 3.8 Gives 13 mpg local driving, It is way low should be 19 mpg. I feel it is due to late shift of last gear it shifts @ above 40mph speed. Just for your info the speed sensor went bad and was replaced in past. Engine is good, It gives me 24 to 26 mpg on highway. Please advise what to do. Thanks
Transmission on 1999 Dodge Grand Caravan
by Gur in Baldwin, NY on September 20, 2010
1 answer 1 comment
ANSWER by Johnny Mopar , September 21, 2010
There are too many variables that effect fuel mileage such as ambient temperature, wind, humidity, altitude, fuel blends, state of engine tune, your 170K mileage, tire air pressure etc. If there is a fuel system issue, it is usually detected by the Powertrain Control Module (PCM) and the check engine lamp will likely illuminate.
COMMENT by Gur , September 21, 2010
GOOD GOD, JUST REPLACED ENTIRE FLUID OF TRANSMISSION WITH CORRECT FLUID AS PER OWNERS MANUAL CAME WITH THE CAR. WHAT A DIFFERENCE, VAN IS NOW GIVING 25MPH HWY, AND 19 MPH IN CITY. THAT'S WHAT IT SUPPOSE TO DO. I SAW VIDEO ON YOU TUBE "HOW TO PUMP OUT THE ENTIRE TRANSMISSION FLUID WITHOUT OPENING IT, THAT IS, DISCONNECT FLUID COOLING HOSE AT THE RADIATOR AND RUN THE ENGINE WHILE YOU ADD THE FLUID AT THE SAME TIME. WHEN BLUEISH PINK COMES OUT OF THE HOUSE, LIKE NEW, THAT MEANS ENTIRE FLUID IS REPLACED. CONNECT THE HOSE BACK, MAKE SURE THE LEVEL OF FLUID IS CORRECT. FOR THIS VAN IT TOOK ABOUT 10 QUARTS IN MY VAN. MAKE SURE TO BUY CORRECT FLUID MINE WAS ATF3 WITH SPECIFIC 4 DIGITS NEXT TO IT IN THE BOOK THAT MATCHED ON THE QUARTS.THOSE 4 DIGITS MUST MATCH TO GET THE PERFORMANCE.