4R55E to 5R55E swap possible?

[NoBoundaries]

Alrighty, my knowledge on trannys is barely par, but I'm curious.

Would moving up to the 5-speed really change your RPM's at highway speed compared to the 4-speed?

Yeah it adds an extra gear, but at the same time, it really doesn't. Right?

It doesn't seem as though it would. If anything, it seems like the 5-speed would take the tranny out faster by putting additional demand on the already crappy overdrive.

 

[Jason_25]

Tim, yes that's kinda what I've been thinking but at 105K miles my tranny feels tight as ever. Also, from what I have seen, most of the 5R55E's on this site have died at around the same time as the 4R55E's. The advantage to the tranny is the lower 2nd gear. Your highway RPM's would still be the same.

 

[yob_yeknom]

Benefits would be slightly increased gas mileage and more power from not making such a large jump in ratios from 1st to 2nd. Less strain on the tranny during that shift also.

Straining an already weak overdrive? The trannies just use the same gears for every thing. It's the combination of which ones are allowed to spin and which ones aren't that determine which gears are the driving and driven gears, which then determins what the output ratio is.

 

[A Quiet Boom]

Well, I finally got the truck running tonight! Turns out the tranny is fine BUT the TRANSFER CASE is bad. It's fine in 2wd but makes nasty noises in 4wd. So the question is this, my brother who has the 5R55E also has a transfer case ('99) for regular 4wd, can I swap that transfer case into my Control-Trac equipped '96? If so will the Control-Trac still work? My gut feeling is that it will since there seems to be a speed sensor on the front axle and it make more engineering and cost sense to produce one transfer case and allow the computer to engage and disengage it when in 4wd Auto mode. Anyone have any knowledge in this area?

Thanks again for the help so far!

 

[yob_yeknom]

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