Transmission Flex Plate/Transmission Heater Leak?

2019 RAM 1500
90,000 MILES • 4WD • AUTOMATIC
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DVDPLMM11
Had transmission replaced 3 months ago at 85,000 miles. Cost was over $5K for transmission with 3 year warranty. Truck started making a high pitched noise and smelled weird after driving. Took it back immediately. They say the transmission flex plate cracked and that there’s transmission heater was leaking. They will not cover under warranty and are charging another $3500. Should I get a second opinion and could the problems be caused by improper installation of the transmission?
Nov 24, 2025 at 4:33 PM
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STRAILER
  • ✓ASE Certified Mechanic
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  • ASE Certified Mechanic
Wow , yep that is on them, a flex plate does not randomly crack 3 months after a transmission swap:

Misalignment during installation

If the transmission wasn’t perfectly centered on the dowel pins, the flex plate gets side-loaded and starts to crack.

1. Improper torque of the torque converter bolts
2. Torque converter not seated fully into the transmission pump
3. Wrong transmission-to-engine spacing
4. Bad engine/transmission support angle

If they forced the transmission into place using the bolts instead of seating it naturally cracks. A flex plate failure at 85K miles, right after a transmission job, is extremely suspicious.

A transmission oil warmer/heater unit mounted with lines.
Leaks happen when:

1. Lines were bent
2. Lines were not seated fully
3. Lines were over-tightened
4. Connectors were damaged during removal/reinstall
5. Cooler fittings cross-threaded

These are also installation-adjacent failures. A heater leak is NOT normal 3 months after a transmission swap. I would bring this up and if they push back it is off to small claims court.

Please let us know what happens. Ken
Nov 25, 2025 at 10:10 AM
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