Zach/90\irocZ

iTrader: (6)

When I go WOT 1st to 2nd shifts hard like it should then when it try's to shift from 3rd to 4th Rome just shoots up to 6000 or so and doesn't shift till I let go of gas a little then it shifts sometimes it does other time it doesn't Also I get a clunk when shifting into reverse or drive that I feel under my seat but I can't hear I only get this only at WOT
It has shift kit and corvette servo I'm not to sure as transmission work was done before I had car and trans has less than 3000 miles on rebuild trans fluid is like new I was going to flush this month trans doesn't over heat smoke etc
I believe when I adjusted the tv cable to adjusted correctly it might have something to do with it as it was adjusted mid way but adjusted correctly for awhile then adjust back to where it was due to shift being not as firm
Thank you

Zach/90\irocZ

iTrader: (6)

i forgot to mention i dont think it does it in regular drive in just overdrive i have to double check

Guest

In drive or D it won't shift into fourth gear, so you won't have this problem in D.

Zach/90\irocZ

iTrader: (6)

i mean it does it in Overdrive not in Drive i have to double check today

but it also always doesnt always do it all the time in overdrive

when im WOT it stays in 3rd and the RPM just shoots to limiter then as soon i let go of gas a tad bit it shifts into 4th gear it doesnt do it every time its ocassional does it

Today ill go WOT in Overdrive and Drive to see if it does the same thing

Zach/90\irocZ

iTrader: (6)

Ok tried WOT in drive and in overdrive Today
In overdrive it did Same thing from 1st to 2nd shifted hard tires chirp then from 2nd to 3rd it didn't shift rpm went up to like 5000+ till I let off gas alittle then it shifted hard heard and felt a clunk like the trans was moving on the trans mount under seat

in regular Drive it shifted fine and hard no issues


What's going on ?

scubasteve

Funny?, my OD is wired manually and does the same exact thing whether it's on or off ? As far as the clunking, check your mounts also the U-joints.

Zach/90\irocZ

iTrader: (6)

How long its been doing that ? Have you corrected it ..Yea I'm Check that tomorrow

midnightfirews6

iTrader: (1)

Pretty sure these cars won't shift into 4th at WOT, even in overdrive, which would explain why you have to let off some. As far as the clunk, first thing that comes to mind is the trans mount which has been mentioned. scubasteve may be right with the u-joints, too.
A trans flush and triple checking the tv cable adjustment may help too, and the cable adjustment will keep the tranny from frying itself as well if nothing else.
Good luck and let us know what you find!

Zach/90\irocZ

iTrader: (6)

Hmmmm

Zach/90\irocZ

iTrader: (6)

Isn't the 2nd shift is shifting to third ? Then it would be 4th OD for the next shift

1st to 2nd
Then
2nd to 3rd Where im have issues ?
Then
4th OD

Or am I'm wrong

abray1

At 3/4 throttle to full throttle it will not go into overdrive. They make an aftermarket thing that allows it to go into overdrive but stock it will stay in 3rd. If it is slipping in 3rd and 4th then the high gear clutch pack is wearing out which is common and usually the first sign that you need a rebuild. I have had it happen to me more than once. I like the raybestus clutches. They seem to last longer. Also look at the 501 boost valve, 13 vane pump, 5 pinion planets, kevlar band and extra cooler. For every 10 degrees you drop your trans temp you add 10.000 miles to it. Synthetic fluid seems to work very well also.

scubasteve

I can smoke em in 1st, get squiggly in 2nd, up to 5k-6k before 3rd. I thought it was just a normal line pressure thing ?

Zach/90\irocZ

iTrader: (6)

Ok when car is in [D] or Overdrive

1st to 2nd

Then shift to

2nd to 3rd Where im have issues ? Isn't this third gear not 4th

Then it will shift

4th is OD if I wasn't WOT so it wouldnt shift till I let go off gas

Or am I'm wrong

I should still have issues in Drive also because it shifts to 3rd fine and firm

Trans is rebuilt already and has fresh fluid still less than 2000miles

antoine

You need a full throttle upshift valve

Zach/90\irocZ

iTrader: (6)

So this is normal not a slipping trans clutch ?

midnightfirews6

iTrader: (1)

the trans should shift hard from 1 to 2, possibly chirp depending on tire width and compound, go from 2 to 3 a little more smoothly, and drop into 4th and the rpms should drop dramatically. The tranny wont go into 4th when youre getting on it unless you have the upshift valve. this is how the tranny normally shifted brand new

Zach/90\irocZ

iTrader: (6)

yea my issue was 2 to 3rd it will stay in 2nd and rpm shoot to 6000 till i let up off gas a tad bit and shift to 3rd hard i wont say smooth but it is firm shift its noticeable but not as frirm as 1st to 2nd but its firm

midnightfirews6

iTrader: (1)

When you say the rpm "shoots up" do you mean it revs freely or it just keeps pulling and won't shift?

Zach/90\irocZ

iTrader: (6)

Hhhmmmm it's like it won't shift the revs go up and stay there's car feels like its pulling not very hard then I let the gas off it goes in gear like I don't even feel it try to go in gear it pulls then when it comes close to shift point rpm still climb till you let off gas a little then it kicks in when I'm back WOT it pulls

Zach/90\irocZ

iTrader: (6)

Another issue came up I was testing car this morning to see if trans was going to act up againg as gear drop down to lower gear to accelerate from 20 mph or so as it drop gear I heard a clunk and now [D] aka overdrive acts like its in neutral but it works and drives in regular Drive

Zach/90\irocZ

iTrader: (6)

any ideas

Formula383

iTrader: (3)

my scenerio is I was doing 70 mp in od then opened it to wot tach climb to 6K and 6.5K (LT1 Manifold) and it would not shift. It hit the rev liminated and I backed off. My rebuilt trans has about 7k on it.

TTOP350

iTrader: (8)

Sounds like your in need of a performance rebuild..

dtedrow

ok anybody know where to get these up shift valves cuz im having the same problem

Zach/90\irocZ

iTrader: (6)

you cant shift wot 3rd to od

you want to WOT shift to OD 4th you need up shift valve not recomended for street

long storie short my forward sprag went out on me heard a big clunk getting on it and lost all forward gears and only had reverse

if your having same issue you prob. need a performance rebuild and from someone you know that does good work unless you do it yourself as most trans shop will reuse good parts instead upgrading to the updated stuff depending on the year of trans

would also recommend trans cooler and run amsoil atf synthetic

morgsie

iTrader: (1)

Not recommended for the street? Ya that's why most Corvette's, F-bodies, and Caprice cop cars shifted to OD @ WOT. If you build the trans properly I don't see a problem shifting to OD @ WOT. I would also NOT recommend any trans shop. Find one that builds them for performance applications on a regular basis. There's LOTS of guys on the net that offer this service. I personally went with Dana's (Probuilt Automatics) Street & Strip rebuild kit and did it myself: 700r4l60e.com.

Zach/90\irocZ

iTrader: (6)

are you sure about that ?

i know good performance trans builders in california, i perfer to do everything myself like you have done

im not here to dispute if your right or wrong its my opinion and that its not needed for strictly for street if your racing then different storie just like you stated built properly

too my understanding no thirdgen had that ability.. i believe c4s had it i could be wrong i dont really look into too deeply so your prob right

most guys just put shift kit and think its a performance rebuild wot into od puts alot off stress on the trans if it isnt built for it
some guys have issues getting out of OD or something i havent look into it as i went into different direction with my build at the time and went t56
if your building a full on trans then thats a different storie like you said

then again i look into every detail before doing a modification and do supporting mods

A properly built trans is going to cost atleast 1500ish

Zach/90\irocZ

iTrader: (6)

700r4l60e.com yea he is a good guy i dealt with him couple of times and talk to him .. he really don built trans anymore fyi but if you personelly ask then i think he will do it he just watch over the other trans builders he has

planing to get my 4l60e stuff threw him

we can both agree it needs to be built right tho to shift wot into od !