I have a 86 f250 460. My p/s pump is squealing like a pig at around 2000 rpms. I believe it's just the pulley can I just replace the pulley and if so do I need to have a double groved one like it has now? Thanks

 

Have you checked the belts (condition and adjustment)?
Does your truck have dual V-belts on the pump now? I don't recall the setup for the 86.

 

V-belts, if not cracked, dry, then just tighten pump..

 

It has duel v belts the look good and seem tight I'll make sure

 

If it is squealing at higher RPM then I agree with the others and bet the belts are loose. But, they may be old and will never quit squealing because the sides are hard. In that case, I think you have three options, shown here in decreasing preference:

1. Replace the belts: BUT, you need to get a matched pair, not just the same part numbers. If matched they'll be the same length. If just the same part number they may be different lengths, like the ones on Big Blue. In that case you'll never be able to tighten things up for the longer belt w/o placing too much strain on the bearings.
2. Use some "belt dressing". This is gooey stuff sold in many parts stores to keep belts from squealing.
3. Lay a round file/rasp in the drive pulley, the one on the engine, and tap it with a mallet - not a metal hammer, but a wood/plastic/rawhide mallet. This will create small serrations in the pulley and keep the belt from slipping. But, it may also wear the belts, from now on, so I'd use that as a last resort.

 

Thanks for all the help

 

#4 in the trilogy:

Your PS pump may be on its last legs. If the bearings are starting to fail, for example, higher than normal force will be needed to drive the pump. A V-belt drive system can only deliver a certain amount of power. If the requirements exceeds that limit, the belt will slip and squeal.

If that is the case, the fix is a new pump. I'd certainly follow Gary's three suggestions first.