92 GMC YUKON New 4L60 BIG Problem?? Help appreciated!

[TerryKing]

Hello Everyone,

Can you please help me understand what may be going on here???

Got a new crate 350 Engine and Transmission from KarlPerformanceParts 2 weeks ago. Got the engine and transmission installed . Engine oil and filter per break-in
sheet etc. Added 4 quarts DextronIII at build, 2 more after warmup, about 2 quarts after first couple miles, and steady then at top of hot. Ran beautifully through the 50 mile break-in and first oil change.

Now I have a sudden and serious Transmission problem and I need your help to understand this.

5 miles after the engine oil change I drove 1 mile down to my installers garage to check on what I still owed him. He was not there and I headed back uphill to home.

About 1/3 throttle, ran nice through first, good second shift and suddenly high RPM. Stopped, and no forward gears at all, any shift lever position.

Reverse works fine.

I have checked everything I can externally. Fluid level is unchanged, top of hot, looks normal. No leaks. Reverse works fine. Cooled overnight. Same problem.

What can I do/check now?? I am in trouble on transportation; the car I borrowed had to go back.. GGrr....

Any comments or suggestions appreciated!

Regards, Terry King ...In The Woods In Vermont [email protected]

 

[jdyates]

Did you make sure the TV cable on the throttle bracket is connected and adjusted properly?

 

[TylerZ281500]

there was no yukon in 92 idt check your tv like stated

 

[1997chevydriver]

there was no yukon in 92

Yes there was......

 

[LoudnLifted88]

if its a 92 its not a 4l60e its a 700r4

 

[TylerZ281500]

Yes there was......

a blazer yes ive never saw a 92 yukon.

 

[TylerZ281500]

anywho start your truck, put it in first see if it sounds like it does anything, then second, then third then fourth. go through each gear and see if anything happens. it sounds like the tv cable adjusted improperly. i dont think a new trans would fry that easy then again it could. alsp drop the pan and see if a jet or needle or whatever may have fallen out.

 

[TerryKing]

Hi Guys, Sorry the notify didn't work so I just got back..

It IS a 92 Yukon. The transmission LOOKS like a 4L60 16 bolts. I can check the numbers. It came from GM Performance (karlperformance).

TV?? The "dentent / kickdown" cable from throttle to right side transmission?? Yes it is connected and previously kick-down seemed fine.

This was a sudden loss of forward gears under moderate load. No response in any gearshift position. Reverse is strong and normal feeling engagement.

I see something about "Sun ??" part breaking??

I'll be towing it into a trans shop so I guess I'll know soon. I wanted to make sure there wasn't some other possibility I didn't think of...

Damn.. ran SO nice with new engine and all just before that!

 

[rhino]

If is won't go forward in any gear, the transmission has to come out. The TV cable will not cause a no forward condition.

 

[TerryKing]

Thanks.. I have talked to GM Powertrain and looks like this transmission will be replaced under warranty. KarlPerformanceParts.com where I bought it was very helpful. I have talked to the GMC dealer with the CASE# and plan to trailer the truck in there Monday. Looks like I will not be replacing that transmission physically by myself!

Other: "TV Cable" - What does that acronym mean??