5.slo

I have a 95 z28 that is having some trans issues. First of the trans is rebuilt by a reputable shop with the normal array of beefed up internals and a transgo shift kit.

On my way home from work I got on the highway and the car would not shift out of second gear, so I babied the car home for 20 miles, once i got close to my house the trans started shifting again, but shifting hard. Now the car shifts normal when I drive normal but if I lay in it it bangs the 1-2 shift very hard and sometimes the 2-3 shift is hard. Alos when putting the car in gear from park or nuetral there is a hesitation and then a slight grind noise before it goes into gear. I have topped of the fluid which was a little low but not bad, also added some lucas trans fix. I have been driving the car easy and when i do it seems like the trans operates normally. From some reading ive done thses symptoms seem to point towards a failed shift solenoid and a epc solenoids for the grinding noise when going from park to drive. Any other ideas or am I on the right track here. Any advise would be great, thanks.

mrvedit

First, I would suggest scanning for both engine and trans codes.
An engine sensor problem (MAF, MAP or TPS) could give you at least some of those symptoms. Particularly the firm shifts and even the no-shift-out-of-2nd. I would carefully the TPS which might incorrectly be telling the PCM you are at WOT.
The grinding sound obviously is troublesome and not consistent with an engine sensor problem.

If the rebuild didn't replace the solenoids, there is only a modest cost in replacing those, but currently I don't think that is where the problem is (but I'm also no expert).

Next I would take it to a local trans shop and have them hook up a pressure gauge and scanner to it that can engage the gears and change the pressure. In another recent thread the OP had some strange trans problems that turned out to be two problems (IIRC one was engine and one was trans). The scan by the trans shop solved one problem and the other was then obvious.

z28newbie

Scan for codes. I bet it's a solenoid

MaroonMonsterLS1

Always check codes as with any problems. Check the resistance in the solenoids by dropping the pan and using a multimeter. Stuck valves can cause poor shifts Also a plugged worm trail or portion of the "brain" (portion of the valve body on the case that looks like those 2 things) can stop fluid transfer, the only thing that makes a tranny work, and therefore kill your shifts. Check ***** in auto trans often need to be removed from certain areas and are often easily missed with a shift kit, even by a good shop. I would check solenoids first, flush the fluid, and quit putting the trans fix it it. That's made to help the clutches from slipping and if you have a new transmission you have new clutches, if the material is gone you have bigger issues anyhow. The trans fix will just lead to more valve body issues if it's not needed. that's my .02 from past experiences and multiple rebuilds of 4l60e's and 700r4

mrvedit

5.slo: Any progress or update. MaroonMonsterLS1 had good advice too.

performabuilt

iTrader: (25)

Note I cant say on Lucas but if you put anything in a fresh trans that it says seals leaks you just made a very very serious mistake as it softens seals and well new seals are soft and so they become mush just FYI. And I agree short of a non movement issue always scan for codes first and soon relatively minor electrical issues with car or tans can rapidly become serious trans issues let go.