Hydraulics are shot, how much to repair? Is it

you should checkout this website www.reliable-store.com that has books on all vehicles, name it they have it.

it covers wiring diagrams, electrical diagrams, fuse diagram, torque specs, PCV, error codes, fault codes, service info, repair info, owner's/service/repair/maintenance manuals etc everything totally..

I have ford expedition and I keep servicing and when needed repair it on my own. worth it !!!

you should checkout this website www.reliable-store.com that has books on all vehicles, name it they have it.

it covers wiring diagrams, electrical diagrams, fuse diagram, torque specs, PCV, error codes, fault codes, service info, repair info, parts info, owner's/service/repair/parts/maintenance manuals etc everything totally..
I have ford expedition and I keep servicing and when needed repair it on my own. worth it !!!

Bad hydraulics (leaking/spongy) and worn out clutch have opposite symptoms. If the clutch does NOT ENGAGE - get the vehicle moving - you probably need to replace the clutch and/or pressure plate.
If the clutch does NOT DISENGAGE - you can't get the transmission into gear, or there is difficulty or grinding when trying to shift between gears - your hydraulic system is not moving the clutch release arm far enough to disengage the clutch.

You'll need to know the exact engine size, but you can start at the link I've attached.
1998 Ford Expedition Radiator Hose Replacement ONLINE REPAIR MANUALS

go to magic mechanic online and ask him--hes a pro w any make

GO ON INTERNET TYPE IN TRANSMISSION REPAIR MANUAL FOR A 1998 FORD EXPEDITION. SHOULD FIND ONE.IF YOU WANT FORD FACTORY MANUAL LOOK UP FORDS TRANSMISSION AND TRANSFERCASE REPAIR MANUALS THEY NOT CHEAP I BOUGHT GM TRANASMISSION AND TRANSFERCASE MANUALS IT COST ABOUT $150.00 DOLLARS MANUAL 8 INCHES THICK ITS WORTH IT GOT EVERY PART YOU LOOKING FOR GOT LOTS PICTURES AND GOOD INFORMATION DONT LEAVE YOU HANGING.

this could be vapor lock if it started shortly after buying fuel. To fix vapor lock, just unscrew the gas cap and release any trapped built up air.
Hope that helps, worth a shot
if this is helpful, please give it a thumbs up to help others, if it doesn't solve the problem, please repost and mention you already tried the gas cap.
good luck,

you can go too auto zone and get a free print out of what you need also

You can go to autozone.com and register for full free online repair manual for you car. You can also view free chilons repair manual at google ebooks.

Feel free to ask any quesitons you have. I have 8 years of mechanic experience.

The only way to find out is to take it to a mechanic who has an engine analyzer and the rubbing could be caused by a loose mudshield (or a dozen other things).