With the RE5R05A transmission being used in vehicles with engine sizes as low as 3.5L to as high as 5.6L, the transmission comes in several different gear ratios to accommodate the vehicle’s purposes. There are differences with some of the internal parts as well. One of those differences is with the Direct Clutch Drum. In 5.6L applications this is a steel drum. Most others use an aluminum drum with a steel sleeve for the sealing rings to seal against.
Steel and aluminum together can at times not cohabite well with one another. Particularly when it relates to pressed parts under the same heat conditions. The expansion and contraction rates differ which can compromise the interference fit. This seems to be the case with these aluminum direct clutch drums. The steel sleeve that is pressed into the back of the drum turns, blocking the feed holes to the Direct Clutches, preventing their apply. This causes a no up-shift into second gear. The Direct Clutch Drum maybe overlooked as being a possible candidate for this condition as most techs relate a direct clutch to third gear not second. But a look at a component application chart confirms that the Direct Clutches are applied for second gear.
To correct this condition requires the replacement of the drum. New runs around $330, part No. 31500-90X0B.
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