Transmission issue? But not sure

[2500avalanche]

So I took my truck out tonight, and ran into an issue. Truck accelerates fine and goes through the paces, but around 75mph I am getting a vibration (pulsation) that gets pretty bad the faster I go. Also, when I am at 60 mph and I hit the gas, boost shoots up to 16lb, rpms go up, but the truck does not accelerate.
When I go home I check the tranny fluid and it is all there and still red. WOndering if it could be the convertor or tranny?
Things I am going to try:
1: Remove prop shaft to see if vibration is still there
1A: If so, I am guess tires are next (Tires have a lot of tread but are about 8 years old)
2: Change tranny filter to see if that fixes the issue

 

[2500avalanche]

So an update:
Went out today.
Went through each gear, and it worked.
Went to D, and that worked
Went to OD and that worked, went through all gears.
Tend to believe it IS NOT the tranny, what could it be?

 

[Sy 0145]

So an update:
Went out today.
Went through each gear, and it worked.
Went to D, and that worked
Went to OD and that worked, went through all gears.
Tend to believe it IS NOT the tranny, what could it be?

Could be tv cable out of adjustment.

 

[2500avalanche]

I think that is what I am leaning too. I have had issues with it in the past. I might look at buying a replacement from sportsmachines

 

[Sy 0145]

I think that is what I am leaning too. I have had issues with it in the past. I might look at buying a replacement from sportsmachines

I have heard of people having problems with that one from sport machines. Maybe one for a 91 S10 with a 4.3 and automatic would work.

 

[gmemony2]

LOKAR also has universal ones. Not sure the length anymore though.

 

[2500avalanche]

Good to know. I will look into them. I know I have had issues with the one on it. every once in a while it seems to go loose

 

[Poconojoe]

I have heard of people having problems with that one from sport machines. Maybe one for a 91 S10 with a 4.3 and automatic would work.

I think a cable for a 91 F body with TPI, might work better since it uses the same throttle body and should be a little longer, since the throttle body is located further front

 

[DaveP's Ghost]

Maybe one for a 91 S10 with a 4.3 and automatic would work.

Won't work. The attachement to the TBI unit is different than the TPI throttle body. Poconojoe got it right. F body.

 

[gmemony2]

If you find one that fits and works, post the part # and where you found it. It would be good to know a replacement that works other than the SM one.

 

[Poconojoe]

The part numbers for the TPI TV cables are 25521263 (85-88) & 10163879 (89-92), IIRC the newer cable is slightly longer then the older one.