: Shift & TCC solenoids in my 5L50E replaced...I have 5th gear again!!!

07-28-13, 02:34 PM
It wasn't anywhere near as difficult or challenging as I though it'd be, having only mechanically-controlled, read: check balls and springs, automagics apart in the past.

Solenoids vs. check balls and springs...solenoids win, hands down, though unlike check balls and springs, they may get flaky sooner than rebuild time.

The three forward shift solenoids were $27 each, plus a metal and rubber gasket, worth every cent of the $27 it cost, and a new filter, because even though the filter was changed a couple of weeks back, I didn't know how much clutch material was sloughed off during the past couple of months of odd 5th gear shifting.

Not much, turns out, but I replaced it, regardless.

This image, yeah, this is scary:


However, when you pull the pan, it looks like this, and is as complicated as you need to get for solenoids:


The rear three, this picture is inverted, looking toward the engine from the rear, require only a thin, flathead screwdriver, unplugging an electrical connector which has a locking tab on it so brittle, it falls off if you look at it sternly for more than about 0.0472 seconds. None of the four I replaced have the locking thing, anymore. It's not like they're loose, though. If any do manage to work loose, I have a plan.

Stick the flathead screwdriver through the items circled in yellow. Makes more sense when you're in there, but these are push-lock retainers. Super simple. That's all which holds them in the valve body. Not only that, but they're oriented in such a manner, you don't have to do anything extra to replace them.

Now, the torque converter, TCC, solenoid. That one does require a bit of extra work, but it's not at all horrible. The location prevents it from sliding out 'cause of the transmission's case. No biggie.

What?! You don't have an ET8 socket?! Slacker!!!!!!!

Kidding, I don't either. I've read the bolts holding the valve body to the case are an external Torx...just when you thought they could not get worse...bolt, but it turns out, and I'm just busted-ass lucky for eyeballing this (or I've done a few too many hack jobs (on my own vehicles)), a 1/4" inch six-point socket is a near-perfect fit! Well, as long as you're not putting 80 ft. lbs. of torque on it....

You don't need to pull them, just loosen about halfway, then the front of the valve body drops/can be pulled down enough to remove/replace the TCC solenoid.

Again, I had issues only with the 4-5 solenoid, but they've all been in there the same amount of time....

I went with the high dollar pan gasket, not knowing if I'd have to go back in here, again. This one, yeah, it's not inexpensive, but wow, is it well designed/built!!!!


I ordered Madtuner's ECM/TCM tweaking wares, today, so I hope to have it all in tip-top shape come mid-week. Yesterday, on a test run, it still behaves a bit oddly, but I think it's re-learning 'cause the behavior changed over about 10 minutes. The 4-5 shift, which no longer existed, before, has become a 4th-converter unlock-3rd-5th-converter lock series of 'shifts'.

We'll see.

edit: I kinda have 5th gear. As long as speed is steady, around 50-65 MPH, and there is absolutely zero incline, it'll stay in 5th, otherwise, it's as if the clutches start slipping horribly, which I don't think it is.

I fear I'm looking at a new valve body, but first I need to run a couple of tests on this one.

For joy.

At least 1-4 is still okay...for now.

Charles Warren
09-26-13, 02:48 PM
what was your car driving like???

01-13-14, 02:22 PM
Sorry for the delay.

It was shifting 'wrong'. Hunting, the occasional flare between gears, eventually 5th gear would slip at the slightest hint of a grade or accelerator increase. Turns out my 2/3 clutches were shot...those may be the same ones for 5th.

This reminds me, I need to sell a valve body... Sigh.