How Can I Tell What's Wrong With My Transmission? (Ford 4.6L, 5.4L)

How Can I Tell If It's Internal Transmission Damage?

The number one symptom that will let you know that the 4R70W automatic transmission, in your Ford car, pick-up, or SUV has internal damage (and which requires an overhaul) is the fact that it ‘slips’.

Your Ford car (pickup or SUV) may present one or more of the following symptoms:

1. Usually (but not always), the PCM will set a ‘gear ratio error’ transmission diagnostic trouble code. Here are some more specifics:
   • P0730: Incorrect Gear Ratio
   • P0731: Gear 1 Incorrect ratio
   • P0732: Gear 2 Incorrect ratio
   • P0733: Gear 3 Incorrect ratio
   • P0734: Gear 4 Incorrect ratio
   A gear ratio error trouble code is the PCM's way of telling you that it knows the transmission is ‘slipping’.
   
   
2. As you accelerate your vehicle, the transmission all of a sudden goes into neutral (in other words, starts to ‘slip’).
3. No 1st gear. Specifically, you put the transmission in drive but no matter how much you accelerate the engine, your vehicle doesn't move.
4. The transmission shifts into 1st gear seconds after you've come to a complete stop causing a very noticeable jolt (this jolt is more pronounced the faster you've been traveling and the quicker you come to a complete stop). The normal behavior is the transmission shifting into 1st gear before you come to a complete stop.
5. No Reverse gear, although the transmission seems to work fine in Drive.
6. When you remove the transmission oil pan, you'll find sediment. This sediment is the friction material that has fallen off the friction discs (which are located inside the transmission).
7. You may find metal shavings in the oil pan mixed in with the sediment.
8. During cold mornings (usually any temperature below 45 °F), Drive doesn't work till the engine/transmission warms up completely.

What will give you the definite proof that you have internal transmission damage (and in need of an overhaul) is removing the transmission oil pan to see if you have metal shavings and/or friction material sediment on the pan.

Transmission With Both Solenoid Failure And Internal Damage

It is possible for your Ford vehicle's automatic transmission to have an electrical issue and internal transmission damage at the same time.

What usually happens is that the internal damage is in the components that create 3rd or 4th gear. What makes the ‘slippage’ (this damage creates) unnoticeable is the simple fact that the transmission doesn't upshift into its higher gears because it's in ‘Limp In Mode’.

From personal experience, I have seen cases where the vehicle had a transmission trouble code and a bad solenoid (or a bad transmission sensor). Yet once the failed solenoid/sensor was replaced and the transmission started shifting normally once more, it started to slip in 3rd or 4th gear.

To find out if this is the case, in your particular situation, you need to:

1. Connect a scan tool and read any transmission trouble codes.
2. Diagnose and replace the failed shift solenoid or transmission sensor (if applicable).
3. Remove the transmission oil pan (if you haven't already) and check to see if there's friction material sediment and/or metal shavings in it.
4. Once the shift solenoid or electrical issue has been resolved (and the pan is back and the fluid topped off), road test your vehicle.

In Conclusion

Hopefully this article has given you the info you need to be able to say that the issue affecting your automatic transmission is an electrical issue or an internal issue (that requires an overhaul).

If you'd like to share your particular experience with the rest of us (which I'll include in an update to this article), you can use the contact form below: