96 Z26 trans help

[GTZryda]

I just got my 96 Z26 with 77k on the road and the trans is acting funny. It has new filter and fluid in the trans

During light acceleration the trans shifts fine.
During moderate acceleration, aka normal driving, from 1st to 2nd and from 2nd to 3rd the hesitates trying to upshift. Car slightly shakes when it try's to shift, and when it does finally shift the shifts are really firm. When I take my foot off the gas when its hesitating trying to up shift, it shifts smoother.

When I go WOT 1st to 2nd shifts fine but 2nd gear will not rev up higher than 4k then shifts into 3rd. But at say 3/4 throttle it will rev out 2nd gear?

Once yesterday at WOT 1st to 2nd Shift it would not shift. I hit the rev limiter and it would not shift into 2nd until I let off the gas to half throttle. This happened only once and has not happened again.

Are these some what "normal issues" of a 4T60E?
And should I get one of those shift kits to fix the issues I have?

[ifixalot]

No not normal, mine doesn't act like that.
You could try a TPS from a different car. Or off Ebay, you can find them pretty cheap.
I think the trans is controlled by the computer in these cars.
The TPS may indicate to the computer how far you've opened the throttle.
If it's not working right, it may be the cause.
Also make sure the vacuum lines in the front of the trans are all good.
I believe frimness of the shifts is controlled by the vacuum modulator.

[Rettax3]

Okay, so I see from the OP that you have fresh fluid and filter already on the car, so #1. below does not apply here. This is just a basic starting-point though, for anyone else who may have similar issues...

1. CHECK THE FLUID. over half of the tranny issues (probably more like 80% actually) reported are due to fluid issues -usually too low, occasionally too high, often just worn out and filthy. Sooo, warm it up, drive it around a bit, and check the level, while running in 'Park' on a flat, level surface. If the level is good, look at the color -it should be a bright, clean red. It should not be brownish or purplish at all. There should be no black speckles in it, and after wiping it off on a clean paper towel, the towel should not have dark smears on it.
2. Check the vacuum line to the modulator -as jskiguy mentioned. A bad vacuum signal to the modulator could casue at least some of the problems you have mentioned. Again, while running, pull the vacuum line off of the modulator, you should hear the engine idle-up a little and be able to feel the vacuum draw on the line.
3. This should actually be #0., but here it is anyway: -Any MIL indications? The 4T60E is obviously Electronically controlled, hence the 'E'. If the computer recognizes any issues with the trans, it should signal the driver by illuminating the Malfunction Indicator Light, or Check Engine Light, aka Service Engine Soon light... Okay, obvious, I know. You would be amazed at some of the things I have had to explain to people at work though...
4. Now it is looking serious. Make sure your 'PRNDL' (gear selector) switch is working okay, and not giving weird signals to the PCM by opening or shorting contacts meant to signal gear selection to the PCM. Most other switches and engine sensors will trigger a MIL if they are malfunctioning, so things like a bad TPS are somewhat unlikely -sorry.

5. A little more specific for you -you say you have fresh fluid and filter, did it act weird like this before servicing? If the filter has come loose inside the pan, it could cause all of your problems listed. Also, if the fluid is the wrong type, yeah I know that is a long-shot, but it could be an issue depending on who did the work... Did you just drain the fluid, swap the filter, and refill? Or was it flushed? A lot of trannys have serious issues right after a flush, because crap gets knocked out of the corners it was hiding in and then gets stuck in a valve or something. Sometimes older automatics just don't like getting the impact of fresh fluid either, after they have gotten used to the 'softer' particle-laden older fluid -it sounds stupid I know, but that is how it is sometimes with some really worn transmissions.

6. A bit more specific for me -the real problem is that it isn't a manual transmission. Swap out that slusher! (sorry again )

BTW, no, putting in a 'shift kit' in it will NOT fix these problems, unless it was simply a loose filter or bad fluid -thereby fixing the problem while installing the shift kit itself. Shift kits actually are designed to make the engagements sharper -more abrupt, harsher gear-changes than stock. Shift kits are NOT repairs, and whether they shorten service-life of the transmission could be hotly debated here, but I say any mod that makes mechanisms bang harder together than normally designed is unlikely to add life to the components... It will in this case increase acceleration performance, but that almost always comes with some kind of a price...

Good luck.

[3X00-Modified]

Well you are right about shift kits in general, but that doesn't apply to the 4t60e kit because it's sold and marketed as a "Shift Correction Kit" It's a valve body service kit that is supposed to correct known flaws of the 60e. BUT if your already having them I can only assume you will need more than just this kit to correct the problems you have.

There is also no way to install this kit without fully removing the valve body and channel plate as well as in the kit it says it should only be installed during a full transmission rebuild and not on an old worn out trans.

[Rettax3]

I would think there are multiple kits out there... What specific brand or source are we talking about, just so everyone is on the same page? No, it wouldn't apply to me or my interests, as the only 60E I have is in my old '95 Z-26, and if I ever have the time to go retrieve it, I will be following my own advice and will swap in a 5-speed (Except for the tranny-mount, everything is ready to go for that, unless I end up stealing the parts from it to convert my Yellow Indy first). Overall, I have not been a fan of auto shift kits when installed in street cars -it seems a little contradictory to me- but I don't care much for autos anyway, so that is really all just personal preference. For some driving styles, there certainly is a reason for a shift kit, especially in such a soft shifting trans as the 60E.

Typically in the older trannys, like the TH350 and TH400 series, the 'kit' is more of a set of directions with a 'drill these ports bigger' and a new (or different?) gasket for the channel plate to my recollection, but there is probably a lot more to it than that, especially on something designed for the 4T60E... A family member of mine used to do tranny work, and that is the gist of what he said about it, although he was probably simplifying it a bit for me in the interests of making conversation.

[3X00-Modified]

There is only one kit for the 60e, and its a TransGo shift correction kit.

Read up on it... It's NOT a Performance shift kit and there is no "performance version" It's a 60e... The most you can get for performance is innovation.

http://www.transgo.com/products.php?cat ... uct_id=220