Body of Evidence
- Subject: Identifying transmissions and valve bodies
- Units: 5L40-E, 5L50-E
- Vehicle Applications: Cadillac, Pontiac Solstice, Saturn Sky, BMW
- Essential Reading: Rebuilder, Diagnostician
- Author: Jeff Parlee
The 5L40-E and 5L50-E transmissions and valve bodies look the same at a glance. On the Cadillac, Pontiac Solstice and Saturn Sky, you can look on the service-parts identification label to identify the transmission by the RPO (Regular Production Options) number.
To identify the transmission, find the identification tag (Figure 1) attached to the transmission case at the left rear just above the pan rail. The 5L50-E was used in Cadillac vehicles only with the 4.6-liter engine.
To identify the transmission in a BMW, look for a G or Z on the tag in the location shown in Figure 1. BMW also refers to the 5L40-E as an A5S 360R.
When you are trying to identify a 5L40-E/5L50-E valve body, look for the three-digit separator-plate code (Figure 2) and the casting number on the second-accumulator housing. The 5L50-E will have a three-digit separator-plate number of 374.
The casting number on the 5L50-E’s second-accumulator housing is 96023532 (Figure 3), and this is the only accumulator that has inner and outer springs. The 5L40-E does NOT use the 374 plate or the 96023532 second accumulator.
One other difference in the 5L50-E valve body is the size of the TCC regulator apply valve behind the TCC solenoid. In the 5L50-E, the valve is the same diameter at both the inner and outer lands, 0.4755 inch. The 5L40-E TCC regulator apply valve has an inner-land diameter of 0.436 inch and an outer-land diameter of 0.510 inch.
General Motors and BMW do not sell the accumulator springs or housings separately. That means that they do not supply identification information for these parts. This valve body has four accumulators that can bolt onto any one of four spots. That would be OK if all the accumulators were the same. Unfortunately, there are five different sizes, and they don’t always go in the same spot on every valve body. Each accumulator has at least one spring, sometimes two, and the springs are not all the same. If these parts are not marked or tagged during disassembly it can be a real challenge to reassemble this valve body correctly. See Figure 4 for accumulator identification.
The information supplied in the following tables should help you assemble these parts in the correct location and avoid shift-feel problems. Just find the table that has the plate code, accumulator-cover numbers and springs that match your parts.
Jeff Parlee is director of product support at ValveBody Xpress.