Truck shifting funny (I think)

[mick883]

I am a rookie to this diesel thing. (late 99 F250 crew cab)

My truck seems to shift funny. When I wind the engine out, 1st gear goes to about 2900 rpms, then 2nd jumps in about 2000 rpms and goes again to 2900 then shifts to 3rd.

3rd gear comes in around 2300 rpms and stays for maybe 1 second and then shifts directly into 4th gear. However, the engine is now "lugging" and no longer "winding out" because 4th gear is coming in at only 1600 rpms.

Do I have a transmission problem??

I have 3000 miles left on my aftermarket warrrenty (bought the truck used) and I want to get it fixed if I do have a problem.

Thanks.

[badazzstroker]

how long since tranny service, i would start by doing a complete drain and filter service

[mick883]

I haven't done a service. I bought the truck in the summer (with 76,000 on it) and now I have 92,000 on it. Is this something that normally needs done? Does it sound like I still may have a problem or might this fix it?