Front End Rattle

[Beav]

There's a couple TSB's floating around Subaru (check www.endwrench.com) regarding steering/suspension rattles on other models. I finally had a chance today to get mine in the air and look to see if the same exists on our cars - it does. The rack and pinion is the culprit, at least in my case. It doesn't appear that it was an issue while the SVX was in production, so that means it'll never be addressed by the factory now.

It's enough of an annoyance that I'll keep an eye out for different things to try and report a fix if I trip over one. It will probably take a while though as I normally don't have a lot of free time, let alone a lot of free 'rack' time at the shop. If the more ambitious of you want to read up on the cause and some of the replacements/repairs, check it out, you never know what might inspire an individual to come up with a solution. Then again, I've been inspired by a few solutions myself...

[Earthworm]

What's the best way for us to check on our cars to see if in fact our steering racks are causing the rattle?

[Beav]

I'm a pretty big guy, so I was able to grab both front wheels at the same time and shake them from side-to-side. It takes quite a bit of effort to do and you definitely need to be under-car to do this. That and be able to step on your fingers when standing straight up...

I would say that if your noise seems to be coming from the front, rather than one particular side, it's more than likely this effect creating the noise. When re-creating it undercar it's very easy to tell that it's coming from the pinion area of the rack.

[CigarJohnny]

Beav, I'm getting ready to take my SVX to the dealer to get some tranny work done on it. Aside from the obvious, is there anything specific I should know or say that will have them check to see if all the TSB work that can be done on it has been done on it? What are some common problems that the dealer should fix free of charge if they had not been done prior to my owning it?

TIA!

[Beav]

You can ask them to check the car's history for campaign work, however I wouldn't hold my breath while thinking that there would be anything they'd be willing to do for free. The car is a little out of date for warranty work.

[CigarJohnny]

I was hoping that TSB work would be similar to recall work. Something that had to be done so the factory could not get sued. Oh well Thanks!

[Beav]

Naw, TSB = Technical Service Bulletin, an article describing proper methods of repair for awkward/difficult pattern failures in specific models. Recalls are normally reserved for safety issues. Some recalls involve non-safety issues that have high percentage failure rates and normally occur out of warranty. How far out of warranty is a touchy subject, but you can bet no OEM will touch one this far out of date.

[svx_commuter]

Beav,

So when you grab both wheels, one in each hand, what do you hear and see?

John

[Beav]

You don't see much as the issue lies inside the rack itself. The sound is definitely the same as you hear inside the car, just more clearly as you're looking straight at the source.

What I find to be peculiar is that I've never heard this type of noise from any other car. Some cars have 'rack rattle' where the actual rack rattles inside the housing (and can usually be adjusted away), but this is totally different. To make the rattle occur you'll notice that you need to run over a bump with only wheel, or both wheels, just at different times (staggered impact.) If both front wheels hit the bump straight-on at the same time there is no rattle. The force needs to cause the rack to react sharply to one side and then the other to create the rattle.

[RSVX]

This seems somewhat similar to my knocking sound when hitting bumps... would my wheels feeling like they might fall off as I back up and turn be a symptom as well?

[Beav]

Nope, not at all. If it feels like the wheels are falling off please have someone take a look at the front end, just to be safe. Some cars do have a 'slip-out' issue when backing up and the wheels turned fully to one side. As long as there's no accompanying tire wear problems it's usually nothing to be concerned about.

I think what you have are two different symptoms. Every SVX I've been in makes the rattle noise (not saying that there isn't any that don't), and judging by the lack of posts regarding failing racks it must not be detrimental.

[svx_commuter]

Beav,

The rack has an adjusting bolt for lash. Would this help the noise? The SM says it should be adjusted every 30K miles if I remember correctly.

[Beav]

Most rack and pinion assemblies have the same adjustment, but I can't recall ever seeing a periodic maintenance chedule for one. Anyway, I don't think this sounds the same as other cars I've heard with that type of noise. It can't hurt to try it though so I may give it a shot one of these days.

[svx_commuter]

Hi Beav,

How do you know it isn't the inner tie rods? I assume you are checking this on a lift with the wheels off the gound and hanging down as far as they go.

[Beav]

Originally posted by svx_commuter
Hi Beav,

How do you know it isn't the inner tie rods? I assume you are checking this on a lift with the wheels off the gound and hanging down as far as they go.

A few years ago my co-workers and I averaged out how many alignments I've done over the years. The number was well over 60,000. Even with a 50% error factor, 30,000 should still provide enough experience to know if a tie rod was bad.

That being said, the problem with the rattle is one that cannot readily be seen because there's no apparent looseness to be found. The noise is obviously coming from the center section of the rack which allows only a few possibilites - as logic would have it anyway. The steering coupling is tight and in good shape, as are the mounts. Either the rack adjustment that you mentioned earlier is off or there's something amiss with the design of the control valve - something I suspect. As the rack is supposedly similar to the Legacy's rack and there are a couple TSBs out regarding similar issues with them, I'm laying my money that the problem lies within the control valve area.