My 94 toyota pulls hard both directions whan in 4wd and my idler arm is bad could that cause my problem

It may be that it is only driving through the front diff. Raise the car up on blocks and see which wheels are turning.

Best guess is worn steering tie rods first. it doesn't take much wear for wheel shake to occur in the 4wd versions. next would be other steering components- idler arm and pitman arm. next would be ball joints- these are probably already needing replacement due to 4wd and age.
Good luck

pit man arm to steering gear nut 186 ft lbs.

pit man arm to relay rod nut 46 ft lbs.

idler arm to frame nut 73 ft lbs.

idler arm to relay rod nut 46 ft lbs.

You could have a bad tie rod end, Idler arm, pitman arm, wheel bearing or ball joint. All of these will normally cause a vibration also. Check by jacking the front end one side at a time and moving the tire back and forth on front and back and in and out on top and bottom. Either watch or have someone else watch the steering assembly for movement and where it is. If there is no unusual movement, it is more than likely an alignment problem or tire problem.

on the wiper arm, there is a cap. remove cap and there is a nut underneath, remove nut spray wd40 oil on the threads that are exposed, then slowly wiggle arm and pull simultaneously to remove.

Alignment has alot to do with the tires not shimmying.. Like zero toe setting. Loose componants like tie rod ends and the idler ar worn. You can ck for excess front end play by holding the front and back of the wheel and pushing and pulling on it, like rocking it. OR have someone rock the steering while you watch where the play is from underneath. By rocking I mean turn the steering wheel back and forth. Look at all th joints and pivot points for excess play, which is, movement not immediate to the rest of the steering system. Tire balance is very important. Wheel hop is a sign of a bad tire and it overtaxes the shock absorber. Shocks don't cause shimmy because they are a vertical movement controlA shimmy is lateral or side to side.Wheel balance weights must be spit. If a 2 oz. weight is needed to balance the tire, Oe once should be on the inside of the wheel and one ounce on the outside directly across from each outher.. Loose wheel brgs will cause shimmy, but they would not last long. Caster setting on the wheel alignment will also cause shimmy. Like on a shopping car. too much caster causes the wheel to start fluttering and is very hard on other componants. This may be why you have worn tie rod ends and a bad pitman arm. Worn control arm bushings and ball joints directly affect titre wear and can only be feltwhen the front end hits a dip and detected by side wear on the tire edges. Summary: replace the tie rod end and have the car aligned. Good Luck, -Ned_ sorry about the book

tire pressure low,alignment jack up the front end and wobble the tires side to side the body lift would not effect this

there is a bolt attached to the idler arm, if you get the right size socket and a good wrench, you have to pull the idler arm. it will pull the entire tensioner and the belt will be loose

A bad idler arm or Pittman arm is a common cause for this problem. Could also be as simple as a tire out of balance. A bad wheel bearing can also cause this. Have it checked out it could cause a very unsafe condition if allowed to get worse.