Timing belt is a 60,000 mile recommended item, should have broken already. Absolutely replace it and the water pump now so you don't get stranded.
O'Rilley's sells Gates timing belt kits fairly reasonable ($75 list, $50 cost), and also Gates hoses. I would replace all of the hoses, and for any non-molded hoses, use higher quality blue or red jacket hose, will last a lifetime. Some of the molded radiator hoses are a shock, quite expensive now. Lower hose from O'Reilly was $30 just the other day (Gates USA made)
Don't use any kind of plug wires other than the OEM Motorcraft wires (p/n WR4068 $36 off of Amazon). They have a much longer/heavier boot and you can get hold of them on the hard to reach driver side plugs. Buy a couple of different types or spark plug wire removal pliers, they are not easy. Use lots of the silicone grease (Dow 4 or equal) on the inside of the plug boots and make sure you feel the "click" when the wires snap onto the plugs.
I use Bosch platinum plugs with no problems. Bought a set of the Autolite platinum plugs and it ran terrible, removed them and threw them away after about a week, and went back with the Bosch (currently using the +4 plug, #4458).
If its a stick shift, change the three rubber plugs on the back of the shifter housing, they should be hard and ready to fall out by now, you will lose your trans fluid and destroy the tranny if they go bad. 3 ea of 1L5Z*7A107*AA about $7 each. I posted pics of the shifter rail plugs in
THIS THREAD, not my thread, but scroll down to posts #6 and #7.
Change the tranny fluid, frequently. I do it every 10,000 mi oil change. 3 qts and a CRC pump and it only takes a few minutes. If it is this old, the shifter bushings are probably shot and need replacing too. Use synthetic ATF in the 5 spd, it will help make it run cooler and last longer. Pics of shifter bushing replacement I posted in
THIS THREAD, not my thread, but scroll down to posts #9, 10, and 11 to see the pics.
Inspect the plastic of the fan closely, between the blades. If it is cracked, get a new one. Fan is E5TZ*8600*A and is about $85 from Ford. Bolts on to the clutch which is a separate item.
Starter, if it is by some weird chance original, or very old replacement, it will have a flat spade terminal for the small wire on the solenoid ON THE STARTER itself. If it does, you want to replace the starter with one with a threaded screw terminal on the solenoid (again the solenoid on the starter itself) since the flat spade type will hang and not release, leaving the starter running after the engine starts up. Even if you shut the engine down, the starter will continue till you get the battery cable removed to stop it. Design flaw. Many starters still come with the stub of wire with a butt splice and a ring terminal to change out the end on the wire. Had this happen a hundred miles from home leaving a Chinese restaurant with the GF. Luckily I was able to twist the battery cable clamp off by hand. Took two tries before it started and released properly. Drove home, called and went and got a new starter the next day. Found out it was a chronic problem on Rangers and Mustangs of the era.
Someone above mentioned fuel filter. It is inside the left frame rail beneath the drivers area. Two bolts remove the bracket from the frame, loosen two worm clamps to get the filter out of the bracket. Two clips to pull out and the hoses slide off. You don't spill much gas, a oil drain pan will catch the small loss. Make sure the new filter has the plastic clips in the box before you start, sometimes people filch them from the box and you are left with nothing. I remove them carefully and save a couple for spares.
I know this is an engine thread, but if you experience front tire wear, esp outer edges on just one tire, your toe in/out is drifting caused by bad radius arm bushings. Install new Polyurethane ones from Energy Suspension and they will never go bad. The old bushings will not look bad and you cannot see any slop in them, but it is there if the tire is wearing all of a sudden and alignment people want to keep resetting the toe in/out.
Differential, you might consider replacing the fluid. Remove the cover and let it drain. Clean the cover and housing surface and put a bead of RTV on it, let it set for a few minutes, install cover and snug up bolts, let it sit, later tighten to proper torque, and refill with synthetic fluid 85-90W gear oil, and you will be good to go.
I have a '91 I bought in year 2000 with 18,500 mi on it, and it now has 278,000. I throw a lot of parts at it, but don't have any problems either. It is now a second vehicle for me.
Charles
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) and I did the Diff fluid when I replaced my rear axle seals and bearings.
