Tranny ???

[tcfurkinusmc]

I recently bought a 78 f150 with the 460 and c6 tranny. The guy i bought it from said it had a 4200 rpm stall which I think may have been a lie. I got the truck cheap and the guy lied about numerous things on the truck. From a dead stop the truck acts like a manual with a slipping clutch. It doesnt start moving good until around 2000rpm and idles at around 900, so I have to give it quite a bit of gas to get it going. I know that a torque converter going bad can cause this, but im wondering if theres a way to see if it really has a higher stall converter or if its just going bad. Any suggestions would help, thanx.

 

[bronc76]

Im not 100% sure on this but from a dead stop and if you have a tach, take off and see how high it goes before it slows down and starts climbing or you may want to replace the convertor anyway if you think its going bad.

 

[Justshootme84]

4200 is a very high stall speed, unless the 460 has been extensively modified to produce high horsepower. You may be able to remove the inspection plate at the rear of the oil pan, and rotate the motor by hand to look for any tags or ID on the torque converter. Even a 3000RPM stall TQ would be too much for a street-driven Bronco, and I would look to replace it with one around 1800-2000RPM. JSM84

 

[krafty]

to get the stall speed from your converter the easy way do this. with the engine running and in drive. hold the brakes hard, and push the gas to the floor for .5 to 1.5 seconds and watch the tachometer. as long as you keep your wheels from spinning, in this brief second the engine rpm will jump up to the max stall speed of the converter.

I was going to use a 2500 stall on my 429 but I wanted to really be able to drive the thing, so I went to stock 1500 and will upgrade before it hits the dragstrip.