Picked up yesterday a 1990 F250, 7.3L 5 speed, 2WD long bad, regular cab "custom".

It runs and drives great, needs a few things you'd expect for a 21 year old truck.

Couple of questions, as this is my first pickup and first diesel.

How do I tell what rear end the truck has? IIRC it's running about 2krpm at 55mph in 5th. Does that sound normal?

Are there any "preferred" places to get parts online? I know with my Jeep, Porsche, and Harley that there's a couple of places that generally have everything at the best prices.. just wondering if that's similar for the Ford.

It's probably in the owners manual somewhere, but what items should I look into as "standard tune up" type of things? I know the fuel filter is a big one. I seem to recall that it's possible to use a filter from a newer truck on the IDI diesel? or is that the oil filter I'm thinking of?

Amsoil lists 9.9qts total capacity.. is that correct? Seems low, considering my Porsche takes over 8 for a 2.4L gas engine..

Basically, any suggestions for a first time owner of a diesel would be good, even though I'm an engineer for Mack Trucks and work with them every day, I'll take all the help I can get. Any threads on here that are good "crash course" type ones to check out?

 

Congrats on the new truck.

You should also post in the diesel specific forums too.

They can give you details on your new truck too.

 

https://www.ford-trucks.com/forums/9...ur-trucks.html Have a read here for capacities. As you can see the engine takes 9.9QTS with filter.
The most important thing is to ensure that the coolanr has an anti-cavitation additive in it. You can get test strips to check if the existing coolant is up to spec.

 

Other than the Ford build sheet, is there anyway to see if it has limited slip?

 

Check the driver's door jamb sticker...It will tell the axle code....

And that in turn will tell you the gear, and LS or not...

 

Ford Axle Code Chart .: Articles Compare the axle code on your door sticker to the codes in this chart (ignore the year column).

 

Thanks for the axle chart!

Looks like it is a 3.55 with the ZF "close ratio" transmission.

What does the close ratio mean (I know what it means technically, but is this considered good/bad, is it the only 5 speed with the diesel, etc)?

Also it says the "capacity" is 6250, what capacity exactly are they referring to?

 

With 3.55 gears and the ZF5 you should get great mileage.
The ZF5 was the only 5 speed offered on those trucks. Close ratio means that as you shift up, the next gear is close in ratio to the last one so no big gaps in ratios.
6250 "capacity" beats me.
https://www.ford-trucks.com/vin-decoder/index.php Maybe enter your VIN here and see what you get.