My GMC Suburban has 97,000 miles, runs fine. My shop says the fan belt tensioner and the idler/pitman arms are loose, and should be replaced. They’re going to show it to me on the rack, but how loose is too loose for these items? What do I look for?
Well, do you trust your mechanic? These shouldn’t be big $$ items, and they do wear out.
It’s a widely advertised local independent shop, but I’ve never used them before and don’t personally know anyone who has. But, they’re auto mechanics…“Trust, but verify”. With their recommended fluid changes in all the diff’s, transfer case, power steering, transmission, and coolant, and adding in new rear brakes (and rear brake cylinders that are said to be leaking) the estimate comes to about $2200…big $$ for me.
Your Sub does not need any repairs that would prevent you from selling it. If normal maintiance is too much you need to take the bus 
You have 100K miles on a 12 year old truck. All the items you listed aren’t really repairs, they are maintenance. If you had the fluids changed in 30K or less miles then the fluid changes might not be necessary. If you’ve never changed them in the life of the vehicle then these items are now vital.
The $2,200 for the total bill seems high for what you are listing. Changing fluid in a diffential should be like $30 or 40. Rear brakes should be about $500. If you want post the item and est. cost item by item and you’ll get some feedback on the reasonable or not costs for the item.
Somehow we’ve got off track on this post - I don’t need advice about taking the bus (the nearest of which is 20 miles away), nor about the costs of repairs or maintenance. What I asked for was advice about how to evaluate the “looseness” of pitman and idler arms, i.e. what’s normal play, what’s “loose,” and what’s “too loose”. Those are the only replies I’m interested in. Thanks.
If appears that you don’t trust this shop. Take it to someone you do trust for a second opinion. The truck is driveable as is so that shouldn’t be a problem.
I had a shop recommend all kinds of stuff, CV joints, yadda yadda; and when I took the same car to another shop they reported all was fine. Drove the car several more years with no issues. Something is telling you that this is a “fishy” deal, so trust your instincts, but take it to someone else to be sure all is OK.
The problem is, it’s not easy for me to tell you how to evaluate your pitman arm, that’s a job for an experienced, trustworthy mechanic. Use the mechanic finder on this web site if you need another, or ask around. As for the fan belt tensioner, if it’s not working, it’ll be making noise and/or the belt will not be tight. But again, if you don’t know what to look for, it’s hard to tell you.
The ball joint section of a pitman arm or an idler arm should have no play at all.
Correction: the FSM gives a 2mm deflection (.078) of movement for the ball joint section of the idler arm, you are probably safe in using this figure on the ball joint section of the pitman arm.
If you don’t like the color comments provided maybe its time for you to MANual up.
For $2200 on a shopping list of stuff I would get another opinion. Did you take this to them for a steering issue? Why did you go into the shop? Focus on what you noticed were issues. Get a second opinion on everything else. I always worry when someone says I came in for one thing and they handed me a big list. Not a good sign. If you asked them to look for anything that might need fixing thats different. If they offered this list unasked then walk away.
I also recommend a second opinion. This URL somewhere has Mechanics files, where people recommend mechanics who have done well for them. This whole $2200 is deserving of a second look even if all that work needs done.
A couple years ago, in Danville, VA, my DIL’s car would not turn over, and a mechanic told them it was a blown motor, though it ran okay when they parked it which is extremely unlikely. He wanted $1500 for a used motor.
I dug into Mechanics Files for Danville. My son had it towed to the most recommended mechanic who found the A/C was locked up. Since it had its own belt on that car, he removed the belt and drove the car back to Texas, I think she is still driving it.
Get a second opinion on the whole $2200.