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Q: Transmission on 1999 Dodge Grand Caravan

Enthusiast 01be16a5a93688912f14755221fb15211b518d9a788cf01b455e03cc1bd585ac
1999 dodge grand caravan 3.8 LE. At what speed transmission should shift to top gear? Mine does at 45 mph. I think it should do at 35mph. Fluid was totally replaced by pumping it out and adding at the same time, while the engine was running at idle in park. It took about 10 quarts when fresh pink started coming out. It has 172,000 miles. No slippage. Engine running excellent. With this late shifting I get 15 miles per gallon, It should 19 in city. On highway it gives me 25mpg, which is more than speced. What should do or replace.
Thanks a million. Will appreciate it.
You have an electronic transaxle and the shift points will vary depending on many factors. Control of the transaxle is accomplished by fully adaptive electronics. Optimum shift scheduling is accomplished through continuous real-time sensor feedback information provided to the Powertrain Control Module (PCM) or Transmission Control Module (TCM).

The PCM/TCM is the heart of the electronic control system and relies on information from various direct and indirect inputs (sensors, switches, etc.) to determine driver demand and vehicle operating conditions. With this information, the PCM/TCM can calculate and perform timely and quality shifts through various output or control devices.

From your description, it sounds like you have your transmission fluid changed on a Transmission Fluid Flush machine. Personally, I do not approve of this method. You need to remove the Transmission Oil Pan and replace the filter(s). Then refill the transmission with MOPAR ATF+4 fluid. This is the only approved fluid for your transmission. Fluids other than recommended can cause erratic shifting, slippage etc. Many shops use fluid color to SELL you a fluid flush when it is not needed, be it coolant, P/S fluid/ Transmission etc. It is there way to make money.
•Better anti-wear properties
•Improved rust/corrosion prevention
•Controls oxidation
•Eliminates deposits
•Controls friction
•Retains anti-foaming properties
•Superior properties for low temperature operation
Mopar ATF+4® has exceptional durability. However, the red dye used in ATF+4® is not permanent; as the fluid ages it may become darker or appear brown in color. ATF+4® also has a unique odor that may change with age. With ATF+4® fluid, color and odor are no longer indicators of fluid condition and do not necessarily support a fluid change.

Chrysler Group vehicle fluid systems do NOT require regular flushing. These systems include: engine oil, transmission oil, axle lube, brake fluid, power steering fluid, and refrigerant. The only exception to this requirement are published in the vehicle maintenance schedules,
Exceptions to this recommendation include only those instances where a failure has occurred and/or the system has become compromised, contaminated or overheated beyond the normal operating range.
Chrysler Group does NOT recommend aftermarket chemicals to flush the engine, transmission, brake or steering systems. Chemicals contained in these products can damage the system elastomeric components, and contaminate the component fluid, leading to loss of system/component durability and service life. When necessary, only the original approved system fluid should be used to flush these components. (This information is shared by all of the major auto manufactures)
Thank you so much for your time. I really appreciate it.
I changed oil myself by disconnecting hose @ the transaxle that come from radiator, started the engine, pumped all the fluid while adding at the same time correct type as mentioned in the owners manual that came with the van (exactly the same ATF4 with 4 digits next to it). It took about 10 quarts when fresh color fluid came out.
Prior to this approximately 1 yr ago filter was changed along with synthetic ATF4 WHICH WAS THICKER than above. Should I change filter again?. You think it will improve?
Thanks again.
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