The trans works good. the 9.5" edge converter locks good, and the TV cable is perfect. There is a TransGo shift kit on it.

Situation: 70 mph freeway, selector lever in OD.
I lift the gas pedal, I move the selector lever from OD to D.
It not backshift from 4 to 3. It stays in 4.
In addition (with the selector Lever in D), if I apply some SLIGHTLY gas (say 5% throttle pedal), the car starts re-gain speed in 4! Applying slightly more gas (more than 5%) and the shft to 3 occurs.
BTW, if under 55-60 mph , moving from OD to D it shift from 4 to 3 instant.
Need help.
-Beppe-

 

I'm the only one with these symptoms?

 

OK, no help..
I'd like to know if you, with a 700R4 (with or withot Transgo shift kit) you can manually move the selector lever from OD to D (with no gas applied) at 70 mph, and have a 4 to 3 shift.
Thanks
-Beppe-

 

Stock rims/tires/gearing?

is it the origional tranny for the car? (meaning its the trans case from your car)

uphill/downhill?

tire pressure?

lots of variables.......

 

??
I'm only asking if you, with a 700R4 can move the selector at 70 or 80 mph from OD to D WITHOUT HAVING THE RIGHT FOOT ON THE GAS PEDAL, and having a shift from 4 to 3.
uphill/downhill, tire pressure hs nothing to do with my question...
Thanks

 

If you are going faster than the governor says the transmission can run in 3rd it is conceivable that it would not downshift. Kinda like the 1st gear lockout above 30MPH.

 

I understand what you are saying, but I'm speaking of 70 or 80 mph, that is much LOWER that the governor signal for 3 to 4.
If I was asking for a manual downshift from 4 to 3 at 130 mph ... you are right, but here we are speaking of only 70 or 80 mph ( an easy speed for third gear).
-Beppe-

 

That depends on weither you put the right springs in you governor, your axle gears, your TV cable adjustment, and you rear tire size. I'd go back and pull the governor cover and check to make sure you put in the right springs. If you put in too light a spring there, it could be seeing that the governor is too far open at a lower speed. What kind of RPM are you turning at 80?

 

I appreciate your way to help me.
Usually i ask here only when I can't find any explanation based on my skill and experience. So the basic checks are obiouvsly OK.
The governor is the right one (not because its "the right one for a corvette"), its right because it shift at WOT at the right rpm level on all gears (around 5400- 5500), part throttle shift points are perfect also.
the 3.45:1 ratio rear is good and the speedo gear on trans is right (It's right because the read speed on dash and on the ECM is the real speed).
The tire size it's correct (around 26") and knowing that the read speed is correct, the tire diameter has nothing to do in the equation.
TV cable is maniacally correct (pressure levels on trans are checked and right).
At 70 mph in 4 the rpms are 2200 (locked TC)
Moving the lever from OD to D the gear used should change from 4 to 3 (it does not happens..) and the rpm should jumps to 3150.
The fact seems to be related only to the 4 to 3 backshift, because I can backshift from 4 to 2 without problems at 70 mph and the tach jumps to 5000...

 

Which Trans-Go kit do you have? I didn't install the new TV Plunger that keeps it in 4th gear over 2/3's throttle so mine down shifts from 4th to 3rd when I'm running like that. It's sounding like whatever was done to null that feature out is the culprit. When I put my 700 together, the first test run revealed I had good 1st gear, sloppy shift to 2nd, no 3rd or 4th. Upon further inspection, I found that I had put the inner part of the boost valve in upside down.

Honest mistakes happen. I'm not trying to irritate you or anything, but even if you have already done so, pull out your instructions on your trans-go kit and read them, and re-read them, then read them again. See if anything obvious pops into your mind, something you remember not looking right, or being overly difficult to install. If after that you can't get it figured out, pull the valve body off, carefully retrace your steps.

Again, I'm not trying to say you don't know what you're doing or anything, I'm sure you do or you wouldn't be so well informed about the workings of the transmission. But sometimes starting at the beginning is all you can do! Best of luck to you, please let me know what you find!

 

The transgo kis is supposed to be the 2&3 kit.
I have not personally installed, but the guy that installed it's the best guy in rebuilding 700R4 .
Are you referring to the TV plunger itself or to the SLEEVE where the TV plunger run into?
I have an aftermarket aluminum sleeve . It is supposed to allow 3 to 4 at WOT and allow high speed in 4th.
This sleeve is what I'll go to see first.

 

Yeah, the sleeve is what I was refering to. Which brand of sleeve is in it?

 

I don't have a 9.5" conv, but my 700 with the trans go will drop from 4th to third as soon as I move the lever.

 

It's a Fairbanks / Superior K015
http://www.oregonperformancetransmis..._Code=SUPERIOR

-Beppe-
----------
Even in deceleration (WITHOUT gas applied) from 70 or 80 mph?
Thanks
-Beppe-

 

Well, it said right there on the bottom of the Oregon Performance page that the 4-3 Detent will "become less sensitive at part throttle..." I assume this could encompass the symptoms you are experiencing as well.

 

Me too I made I jump on my seat when I read: " 4-3 Detent will become less sensitive at part throttle".
But, this statement is only because people that purchases this sleeve are tired by the fact that at higher speed in OD "a little presseure on the gas pedal more than 1/2 and it will downshift".
With this sleeve, you can depress more the gas pedal without the downshift occurs.
-Beppe-

 

where you able to figure out the problem yet?
curious to know how you solved it
thx

 

I have no time
I haven't solved the problem. My next step is to add a .500 boost valve and a .296 int-rev valve and I'll try to change the aluminum sleeve .

 

i also have a shift kit in my rebuilt 700r4, and i ofter down shift at 100km in 4th gear down to 3rd, but i take my foot off the pedal so when the rpms jump me giving it extra gas wont rev it super high

 

I'm not sure that I have 100% understand what you are saying, but I can confirm that If I move the selector lever from OD to D when I'm 100 Kph (62 mph) the gear selected remain the 4.

I can confirm that when move the lever from Od to D my right foot is NOT on the gas pedal.

But, If I move the lever from OD to D and I have the the gas pedal slightly applied (say 5% or 10%), it perform a 4 to 3 shift.

Yesterday I made a little trip.

If I move the lever from OD to D it stays in 4th gear.
Then If I continue to slow speed (remaining with the lever in D and the gear is always the 4) when I'm crossing 52 or 53 mph it will put the 3rd.

So I found the limit of speed. Over 53 mph and I haven't downshift from 4 to 3 moving from OD to D.
Under 53 mph it works.


-Beppe-