As a brief back-story: I bought my blazer with no 3rd/4th. The precious owner didn't understand the TV cable setup on 700r4's and just clipped it on. There was another issue which contributed to the 3/4 failure which I'll go over in a minute. When driving it would just freespin on the 2>3 shift. I could manhandle the throttle and get 3rd to bit and hold however it would never even attempt OD.

First let me say that this is my 4th transmission I've rebuilt (two 700r4, one 4L60e, and a 4L80e) so I am by no means an expert but I believe my understanding of them is much above average.

Going back, upon r&r I found the 3/4 piston had pinched and torn lip seals. Trans got all new lip seals...well all seals in general, and was rebuilt. Governor was also serviced with a new gear and valve was free. The Valvebody valves seemed to be tight occasionally, sometimes getting stuck in their bore more than normal (I think) while I was servicing and cleaning the VB.

New transmission is together and in the truck. The issues at that point are:

1) I have 2nd gear starts in OD. I can manually select first and it gives me first.

2) there is a fair amount of 2>3 flare. Id say 500rpm surge at full throttle. 3/4 Clutch pack was set up at 0.033

3) still no 4th gear. Trans stops at 3rd. Only difference between the OD and 3 position is engine braking in 3rd.


On a whim, I went to my local trans parts shop and bought a green box Gil Younger (TransGo SysKoKal system calibration) kit. I have installed the big blue box reprogramming kits before, however this kit had so many springs that it was honestly overwhelming. I did my best on it and after reassembly I did get OD but everything seemed softer all around and it was still starting out in 2nd gear. I am considering getting a used Valvebody and cleaning it up, but would still need some assistance with the syskokal kit if anyone knows it well enough to help. I know this is kind of long winded but thanks to those who read it and can help!

 

I don't think I can help much as i've only done one trans.

That sounds like a control problem. Did you scan it for codes?

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No way to check for codes, there is no computer in the whole truck. The transmission is controlled by valving and a cable for line pressure and shift point influence. Thanks for trying to help though!

 

Ok - I checked your sig. and it looks like you have a k5 with a 454 swap - And with no computer it must be carbed - what carb is on it ? The orig Rochester ? If not what carb. is on it and is it compatible with a TV cable without a cable kit

 

Original Rochester QJ with correct geometrical TV attachment point.

 

you have prob all ready checked them but check the cable for no dragging and also the spring under the TV valve it could be getting weak. I had a weak spring in the 2004R in my beefed up RX7 with a 350 in her and it made her miss gears Ect.

 

Cable was indeed checked when trans was out. TV valve was fitted with the new nonstick spring and longer plunger spring. Needless to say I went back and checked all that 3 times anyways just to be certain lol