700R4 Shift Problem

[hammer]

Ok 89 suburban 350 fuel infected 700R4 will not shift until 30 mph to 2nd then 50 mph from 2nd to 3rd. 3rd to 4th don't know but It will down shift from 3rd to 2nd at 49 mph and 2nd to 1st at 29 mph where throttle position doesn't matter.
Now that I think about it one of my freinds S10 blazer 700r4 has the same problem but it is driven every winter no problems.
Please help thanks

 

[heavy4x4]

Check your T.V. cable. (No not the T.V. in your family room) I think T.V. stands for "throttle valve"???
It runs from your throttle linkage, down to the tranny, and inside. In earlier years, all it controlled was "kick-down," but in that year 700-r4 it controlls the shift points both up and down. I'm guessing it's either broken, disconnected in the tranny, or severly out of adjustment.

 

[imiceman44]

Other than the throtle cable I am not sure if the 700 has it but the 350 and 400 have a vaccum modulator that if leaking vaccum or the hose is off, will do that.
Mine was unhooked and I thought the tranny is dying and needs a rebuild, then I was doing a check up and I saw the hose and hooked it, now it runs very smooth.

 

[Mr. Jimmy]

I don't think the 700R4 has a modulator valve, sounds like the TV cable to me.I believe the Haynes manual covers this adjustment which is fairly simple, should be able to push locking tang in with a small screw driver (on the bracket for throttle cable) and pull accelerator linkage to wide open position for basic adjustment and go from there to get shift points set correctly.

 

[hammer]

no vacume on the tranny. First thing I checked thought that also

 

[Highlander]

I would check the T.V. cable the 700R does not have a vacuume mod.

 

[transcore1]

Sounds more like the govenor, The TV changes downshift more than anything. The govenor makes the gear changes happen by centrifugal force. It is located under the 3 inch round cap by transmission output.

 

[imiceman44]

You're right I forgot about that.
If the governor valves get sticky or the springs are broken or tired you could have that problem.
You said you had to accelerate a lot to get it to shift, then my guess would be it's sticking.