135000 miles
New injectors
New plugs and wires
All new O2 sensors
New Catalytic Converter
Oil and Trans fluid change now due

Truck has been fairly well maintained with regular fluids, etc.
Recent smell of trans or pw steering fluid, but no noticeable drops on driveway or loss on dip stick.
Odor most pronounced after a freeway drive.
Rpms are way off. Down shifted from D to 3rd today on freeway. No change in RPMs at all.
Rpms are 2200 at 53 and 2500 at 60, but that is normal for 3rd gear.
Usually, rpms are 2000 at 70mph dead on.

It seemed that the odor appeared after the recent replacement of converters and O2 sensors by Pepboys. But, not certain.

Truck seems to be shifting into gear a touch harder than normal with a noticeable thud.

What would be your best guess as to the cause of the truck not shifting up to 4th at freeway speeds?

Where should I begin to look?

Thanks very much,

Tracey