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What are the symptoms of bad idler arms?

01-07-2006, 08:44 AM
I just picked up a 92 astro with 180k for $150...Solid (for being a michigan van) but wouldn't start...I got it home, and realized it was a bad battery cable.....Dumb people make life enjoyable at times I guess :rofl: :rofl: Anyway, upon test driving it the best way to describe it is appearing "unstable"...Hard to keep on the road....Balljoints seemed ok, little bit of play but not much....I hear these vans need idler arms as routine maintenance, but not sure what to expect if this is the case...I had somebody else tell me steering gear box....Kinda drawing straws now, will take a look at it later....What should I look for? Thanks i advance! :biggrin:

01-07-2006, 12:47 PM
A few years ago I bought my sister's Astrovan (it was about a 1988 van I guess). It had about 140K miles on it at the time. She had new idler arms put on at about 60K miles, and had been told by the people at the tire place that she needed new idler arms again. The van drove good, so I didn't bother getting it fixed. Later I was told that the idler arms are spring loaded, and that some mechanics would show people the movement when the spring was compressed, and scare them into getting unnecessary and expensive repairs. I drove the van until it had 250K miles on it, and then traded it for a 1995 Astrovan (which I still have). The 1995 has 260K miles, and the original idler arms (drives and handles very good). I don't know what is wrong with your van, but I would look for something other than bad idler arms based on my experiences. Good Luck.

01-08-2006, 02:31 PM
I agree. Be careful what the machanics say. I bought a new set of tires the other day and just for kicks asked the guy if he could check out some of the suspension components before doing an alignment. He said he couldn't because the upper control bushings and idler arms were bad. He proceeded to show me how bad the idler arms were by moving the disks back and forth. It appeared to me that there was no way that he could tell the idler arms were bad by what he was doing. After 210k miles I have never had it aligned and my tires still wear evenly. I am at a cross roads whether or not to change them. If its not broken.... After some research on the former posts, I found that there is a 1/4" allowed in the idler arms. The chilton manual even tells you how to check for the 1/4" but looks like you have to remove two bolts that attach it to the frame. I would suggest doing a search on this site and on the internet to see what else you can find.

In my experience a proper balancing of tires and alignment usually does the trick. I would start there.

BTW, they were a little surprise that day that I do all the work myself considering how I was dressed. Thats why I never go to a shop for mechanical items.

01-09-2006, 07:04 AM
[My wife ('94 Astro) had the unfortunate experience of having an idler arm pop loose while turning a corner- just one block from the repair shop- they put on the Moog heavy duty ones. The steering was unsafe- wheels were no longer turning the same direction- she was able to make it to the shop.

Also had the rear end limited slip differential locking pin back out and come loose- jaming up the rear gears- again going around a corner from a stoplight- both rear wheels immediately locked up- skidded to a sideways stop. I towed it home and put in a NON-limited slip third member, the pin was loctited at the factory but it still came loose- this was at about 251,000 miles- 3 yrs ago I have 320,000 on it now- doing fine......

01-09-2006, 09:15 PM
There seems to be some misunderstandings about steering linkage, and diagnostics in this thread that I will try to clarify. Idler arms are NOT spring loaded. The OEM idler arms on the M body (Astro/Safari), where the idler arm pivots, was designed as a threaded connection. This connection needs to pivot back and forth while steering the vehicle. Over a period of miles these threads will wear, causing the connection to loosen up. This loosening ends up as excessive play in the steering linkage. Take into consideration that these vans have two idler arms, (very few vehicles have two), so wear shows up twice as fast. One method of testing is to raise both front wheels off of the ground and simultaneously pull the front edges of both tires toward each other, then away from each other. Ideally, there should be zero play in order to maintain a constant toe-in adjustment. This method will test more than just idler arms, it also tests tie rod ends, center link, etc, all steering linkage play of all components combined. Typical toe-in specification is between 0" and 3/16". Obviously if there is more total play than 3/16", you will never be able to keep toe-in within specification while performing an alignment. Toe-in is the most critical adjustment angle involved in front end alignment concerning tire wear. This method of checking steering linkage is done as a preliminary check. If overall play is excessive, then the technician needs to find out exactly what part is excessively worn. Another method of checking idler arms for wear is to grab the arm where it meets the center link and move it up and down. There is a specification for maximum deflection in Haynes and Chilton manuals. If you ever have your OEM idler arm off the vehicle, un-screw it, you'll see what I'm talking about. Regular chassis lube jobs help, but the combination of natural stress on the arms, and wear, it's not a matter of if, it's a matter of when are they going to wear out. Moog manufactures replacement idler arms for these vans and they do NOT use a threaded connection. They also warranty their parts for as long as you own your vehicle. Any questions, Iím ready 

01-09-2006, 09:18 PM
to check an idle arm the van needs to be on a flat surface. to ck have someone start the van while you
are under the front end have them turn the steering left and right you will see uneven movement. i have found inner & outer tie rods cause
this. to ck just push up or down any part that has any movement is bad only replace the ones with the most movement. the reason you ck on a flat surface if you jack it up it will put a load on your front end.

01-11-2006, 09:37 PM
What kind of shape are the shocks in?
also, what's the condition of the bushings on the anti-sway bar? and for that matter, what shape are the tires in?

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