Is this normal?


Active Member
Jul 10, 2008
Installed an EA stage 3 trans (2.57 first) and PTC 9.5NL and have a few questions. It replaced a tired trans and non-locking D5. Whether it wasn't locking due to solenoid or burned clutch I don't know - I installed Husek's pan on it and the bottom was all mud. Anyhoo, some different behaviors:

Old, put car in reverse, car pulls out of garage (no driveway) and I can straighten it out on street. Nothing but brake pedal. New, put car in reverse, car starts to pull out and just stops midway through turn. Apply more throttle than I would expect to continue to straighten out.

Old, put car in D and, when cold, it pulled hard enough to shift into second, never touching the throttle once. New, put car in D and, eh, it sorta goes. I ASSume this is just what a higher stall feels like (I've been a clutch guy my whole life, fwiw)

Old, 1-2 shift was barely noticeable, 2-3 shift nearly non-existent. New, nice 1-2 shift, 2-3 shift feels... different, don't know how to describe it, and I don't know that it's bad - just different than the 1-2. The first couple times out it did some weirdness at 2-3 shift, like in and out really quickly, but that has settled down since then. The 2-3 shift also comes sooner than I'd expect. This is all light/med throttle stuff so far, btw.

Old, on freeway, spun 2400rpm@70 (3.42 gear, 26" wheel) - 15% slip. New, 2150@60 (3.23 gear, 26" wheel) - 27% slip. New, 2300@70 (3.23 gear, 26" wheel) - 16.6% slip. This kinda surprised me, all the low speed stuff I could have chalked to stall speeds, but an unlocked D5 slipping less at freeway speed? Speed measured with GPS, btw.

Just looking for some feedback. I'd read threads where people claim they didn't notice a difference from stock, or only 50-100 rpm from lockup on freeway and I'm concerned something isn't quite right.
First question. Have you called and talked to extreme? This is very important. Call him now.

What is the rated or what were you told the stall speed should be?

I am certain Mr Diers can get you squared away, bur if you havent contacted him he doesn't even know there is a problem.
It sounds like the combination of having a higher stall [ you didn't state how high it was] and having a NL and lower gears [3.42vs.3.23] which is minimal but may affect the slip a little more at freeway speeds which is normally a low load situation and rpm will climb some when going up an incline/hill, how much it climbs depends on the grade percentage and stall speed you have in the car.

A 2800 stall will slip less than a 3400 stall at light throttle [low load] and the speeds you posted as it is closer to its rated stall.

I would do what TexasT said and call Lonnie. He can explain to you whether what you are experiencing is normal or if you have a potential problem that needs your/his attention.
I would verify pressures before doing any more driving. If you found mud in the pan that's not good

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Also check TV cable adjustment it is critical to longevity and how it shifts along with line pressure.
I called Lonnie yesterday and PMd Dusty this morning.

When installing we dropped the pan to verify TV adjustment and checked pressures. Some pressures read about 10psi on the high side. The mud was from dropping the pan on the original transmission and that's what started me on replacing the converter and trans.

Another thing I mentioned to Lonnie was on the old trans, after warmed up was somewhat whiny. The new setup, after warm, is *very* whiny. Also a slight "howling" sound on the freeway with *any* amount of throttle. Lonnie said to verify the whining occurs in P/N or not, that would indicate where the sound is coming from. Pretty sure it occured in Park, but going to double check.
You're in good hands with Lonnie and he will get you fixed up right.

Just do what he tells you and it will all work out in the end.
What your experiencing is the difference between an 1800 stall (stock) and a 3000 stall. Since your not familiar with automatics, this is how they work. When you raise stall speed it takes more engine rpm to move the car. The newer converters drive way better than what we had years ago. They felt like 4000 stalls.

The shift feel could be due to improper TV cable adjustment but even when right, the 2-3 shift will always feel softer than the 1-2. 2-3 often will feel more like a soft change rather than firm until your heavier into the throttle.

As for highway rpm's. Again a stock converter is a much lower stall speed so cruise slippage will be higher with a higher stall converter. Like had also been said, the 3.23 gear will cause even more slip. With the 3.23 you have lowered the cruising rpm further away from the stall speed and also put more load on the converter which will cause slip to go up.

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