I was wondering what Trans this is because the previous owner told me it was a NP. Hopefully I have a good setup!

Here is a picture of the Tag, and the Tag of the Transfer Case.

e3ta7003 va fe

6 11 85 The FE could also be fd, f6, fg, f5








And the Tag on the transfer case,.
208f 1
e4ta7 a195ca






Does anyone also know running RPM's of this truck at 60 mph? I am guessing around 2500? Thanks in advance for any input.



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1984 F250 4x4 4.9L

 

From what I found with a little searching (Hint - you can do that) the tranny is probably an NP435. But the transfer case is certainly an NP208 as it says that on the tag. That's the combo I have in one of my trucks and it works very well. However, the 1:1 top gear still leaves the engine spinning rapidly at 60.

As for how fast, we can't tell you that because it is dependent on axle gearing and tire size. The rear differential should have a tag on it (in about the 10:00 position when looking from the front) that gives the ratio. Put that and the tire size in this equation: 337 x speed(mph) x transmission ratio(is 1 in 4th gear in your truck) x axle ratio / tire height in inches = rpm. Or, for a bit more accurate way, go to Tirerack.com and find your tire or tire size and determine the rolling diameter. Then take that to one of the formulas you'll find in the techstickies at the top of the threads list and you will get a closer answer.

 

Get under there with some PB Blaster or some WD40 or even soap and water and clean BOTH sides of the transmission underneath. Passenger and drive side.

If I remember correctly, the tag on my NP435 was on the passenger side next to the PTO cover (above it, I think).

Most of the trucks like yours and mine that have a NP208 transfer case and a 300-6 will have a NP435.

If you can, look on your door jamb sticker on the driver's side pillar of the cab door. Your transmission code should be "A" if you have the New Process 4-speed. Assuming nobody has swapped your transmission (which is highly unlikely, because the 208 is a married transfer case).

On your transfer case tag, you'll see "Ratio: 2.61", that's the low range in 4-wheel low of your transfer case. 208F is the model. I'm going to go ahead and assume "84" is the year of the transfer case, which matches the year of the truck.

I never did take pictures of my transmission/transfer case tags... might have to do that later today.

To determine what RPM's you'll be turning at a given speed, we'll need the rear end ratio of your truck, your tire size, and what speed you're running.

 

Here's the tag from my NP435. This is on the passenger's side, and that is the PTO cover the bolts it is under are holding on.

 

NP435s have an aluminum shift tower, which you may be able to see. They also have "NP" cast into the side of the box.

Pictures:

Domestic Truck Tranny Guide