That I am aware of, there are a few reasons for bent rods in those engines. About ten years ago I got wind from a dealer that the reason that a lot of the later produced 3.5s bent rods is b/c M/B actually started using a lighter weight rod in a effort to improve efficiency. Those lighter weight rods just weren't up to the task of taking the pounding that the heavier rods would. If caught beofre further damage those engines could be torn down and be rebuilt using the older heavyweight rods and be fine.

The other common occurance is for coolant to make it's way into the cylinder causing a rod to bend. That isn't so much a 3.5 problem but a 603 problem. If a small amount of coolant can make its way into the cyl it will erode the block and head due to what I'd call coolant detonation. If enough coolant makes its way into the cyl, bye bye rod(s)

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90 300TE 4-M
Turbo 103, T3/T04E 50 trim
T04B cover .60 AR
Stage 3 turbine .63 AR
A2W I/C, 40 LB/HR
MS2E, 60-2 Direct Coil Control
3" Exh, AEM W/B O2
Underdrive Alt. and P/S Pulleys,
Vented Rear Discs, .034 Booster.
3.07 diffs 1st Gear Start

90 300CE 104.980
Milled & ported head, 10.3:1 compression
197° intake cam w/20° advancer
Tuned CIS ECU
4° ignition advance
PCS TCM2000, built 722.6
600W networked suction fan
Sportline sway bars
V8 rear subframe, Quaife ATB 3.06 diff