What did i break

I am not the sharpest tool in the box. I was driving my 1979 f250 with a full load of fire wood going about 45mph when I shifted it from drive to reverse (I thought I was in 1st) the truck mad a loud whining sound then refused to go on. Now when I shift it in gear it feels like it wants to move and if I revved up high it will rock back and forth. A friend jacked up the rear end with the wheels off the ground the tiers spun in all gears including park and I was told they could stop the wheels by hand with the car in drive. He then took the cover off the rear end and found it to be low on fluid but no signs of damage. Can someone tell me what I broke? Thank you for your time

You broke your truck’s transmission.

Yes…yes you did.

Even a C-6 has its limits.

The good news is that you didn’t break your brakes.
The bad news is that you did break the transmission.

What did you BREAK? You BROKE your transmission. There is a good reason that it is rather difficult to move the gear selector from drive to REVERSE…it usually has a lockout that must be defeated before the trans will allow you to go into reverse…it should have an active lock solenoid that completely does not allow you to enter reverse if any forward motion is detected at all.

You broke your transmission…Case closed. Sorry for the happy news but this put the BRAKES on your day…When you decided to BREAK your Transmission.


" tiers 9sic) spun in all gears including park" - OP

Sooooo is this an automatic?
Nomatter. Your tranny is busted. Exactly what broke can only be determined by opening it up.
Honestly, I’d look for a used tranny from a boneyard.

Thank you all for your input and translating my horrible spelling and grammar did i mention i am not the sharper tool in the shed lol. my dad and i thought it was c6 but a friend of mine swears it was the rear end he thinks broken axle because the wheels spin when in gear with no load but we have not removed them to check another question would 500 be a far price for a rebuilt c6 with 50 miles on it?

Is it possible that it is just a broken universal joint? If so, this is a lot cheaper than a replacement transmission.

You stated that when you revved the engine you could feel the vehicle trying to move… Akin to when the clutches inside the trans are slipping a lot…and more rpms sort of rock the car as tho it is trying to move forward. None of that would occur if you had a snapped axle shaft…easy enough to rule out as well if you must but…just jack up the rear end while in park… Rotate one of the wheels to see if the other spins…if it does…no snapped axle. The other method will be to put the tranny in neutral while the rear is jacked up and wheels off the ground and then manually spin your drive shaft by hand…you will see the wheels moving under Hand Power…if both spin…no snapped axle…if only one spins…Hold that one wheel stationary and spin the driveshaft again to see if the other is powered. The last is to be in neutral …hold one wheel stationary and spin the other wheel to see if the driveshaft spins… this will verify your axles and driveshaft.