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What parts to you consider “time expired” after a certain time/track cycles and what timeline do you use for replacement?

55
90
Exp. Type
HPDE
Exp. Level
5-10 Years
Nova Scotia
Was running a track day yesterday and watched a tube frame stock car hit the wall after the drivers rear coil over mount failed. I’m familiar with concerns about ball joints after a certain number of years being a potential failure.


What other parts do you consider as “time expired” and therefore get replaced after a certain timeline to avoid these types of failures?
 
1,118
1,086
In the V6L
What timeframe would you use for wheel bearing replacements?
It depends on the parts involved. Factory parts tend to fail relatively gracefully, they wear out progressively and that's why the factory uses them. Worn wheel bearings will have a bit of slop if you wiggle the tire. Ball joints and bushings can be checked with the car in the air - pry on the attached parts to see if there's movement. Factory parts rarely fail catastrophically if you check them regularly and replace if they show wear. Aftermarket parts, like spherical bearings and so on, usually get noisy before they fail, but they are capable of just coming apart at a critical moment. Again, if you pay attention to little noises and look for anything that looks loose you'll be ok. I do a roll-around under my car before every track outing, looking for leaks, bits of OPR stuck in vents, loose parts, etc. Last year I found that one of the jam nuts on my adjustable rear toe link had worked loose - the witness marks didn't line up on the visual inspection and it was only finger tight when I tried to move it. That's the stuff you want to catch.

The failure of the upper suspension pickup point on the race car that you witnessed is a different situation. Those cars need to be gone over thoroughly every time out. They are purpose built to be light and stiff, and sometimes fatigue can set in, cracks develop and things break. Thing is, they're cheap to fix - a new fiberglass body for a "Nascar" tube chassis is cheaper than a GT3 windshield.
 
4,835
5,584
Big thing is inspect the car before every track day. We "rock" the suspension and wheel bearings every time the car comes in. It's my job to inspect the wheels, although many forged ones can be safely straightened.
 
55
90
Exp. Type
HPDE
Exp. Level
5-10 Years
Nova Scotia
One part I’ve wondered about is flexible brake lines. I’ll be changing mine before any further track time given they are 16 years old. But do folks have a timeline where they consider them unserviceable?

As for pre event inspections, I found using TorqueSeal markers on critical nuts and bolts a lifesaver on my tube frame car. Time to dig it out of the race trailer and start again.
 
55
90
Exp. Type
HPDE
Exp. Level
5-10 Years
Nova Scotia
For track use original brake lines are not adequate. Rubber is softer and can produce a soft, spongy pedal. They are also more prone to breakage if debris is thrown into them. At age 16, change asap.
While I agree that mine are in need of changing, I certainly think that for most novice track participants, OE style rubber brake lines are just fine in the first few years of their lifespan.

If I recall, the rate of breakage for braided stainless lines after only a couple years is much higher than OEM rubber lines. The stainless lines I bought for my Subaru recommended changing every 5 years I think due to degradation.
 
It’s a totally different ball game but in lemons they prefer the oem style rubber as it’s easier to see they are dried out / rotted / cracking. Harder to tell with the stainless ones. 100 crap cans on the track requires different approach. With well maintained serious track cars it makes more sense to trust participants to not run stainless past recommended life.
 
1,118
1,086
In the V6L
I'm too tired to write a whole technical post on this, but here's the short version:

There are three types of brake flex hoses - OEM grocery getter, OEM performance and stainless aftermarket.

The OEM GG ones are long-lasting but not particularly good at preventing expansion under pressure.

The OEM perf lines are excellent. OEM 2012+ Boss 302, 2013/14 GT500, GT350, 2020+ GT500 lines have about the same expansion characteristics as stainless steel lines. It's a special product from Goodyear (as I recall) and there's no reason to change them. If you look at how Ford has terminated them at calipers there's a long length of steel tubing. That protects them from heat, and more important, it protects them from twisting.

Aftermarket stainless lines. It's a total crapshoot. Teflon-lined stainless tubing doesn't handle end-to-end twist well at all. If these lines are twisted end-to-end, they'll fail fairly quickly. Some products, like Goodridge for the S550, follow the Ford OEM architecture and layout - the Ford engineers designed the OEM brake flex lines with zero twist and the Goodridge lines are made with the same shape and they don't twist either. I can explain how it works but I won't do it now. Suffice it to say that if the S550 replacement line doesn't have a length of rigid pipe at the caliper that puts the flex line termination up by the side of the strut then the the lines have a limited lifespan in the vehicle.

Update: Okay, so not so tired now... The bit I left out is that the OEM lines on the FP S550's are either too short or the wrong shape for most aftermarket calipers. That means you're kinda stuck with aftermarket brake lines if you install someone else's calipers. Most of the "DOT" stainless brake lines that come with a kit have a plastic jacket (keeps dirt out so the teflon doesn't wear and fail) and the ends are properly strain relieved, etc. Thing is, unless they more or less follow the OEM pathway from the caliper to the hard line, they'll twist and that'll wear them fast. Here's the front axle pathway in the GT350:

1653670160365.png

Notice how, from left to right, the rubber line starts by going up, then turns down, and then up again where it terminates on the hardline fitting. If you're curious why this matters, here's how to demonstrate the effect. Take a piece of hose or a short USB cord, form it into that shape and then rotate one end relative to the other, the way the brake line in the picture would rotate with steering inputs. You'll see that the up and down curves bend and change shape, but the hose itself doesn't actually undergo any twisting from one end to the other. That big mounting boss on the caliper and the length of steel tubing make sure that the end of the flex section is exactly where it has to be to ensure long life and minimum stress. A stainless flex line that's flex all the way down to the caliper boss won't be able to hold that shape and it will experience some twisting as a result.

So, that's the rest of the post.
 
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55
90
Exp. Type
HPDE
Exp. Level
5-10 Years
Nova Scotia
Why start learning with a softer pedal? Brake feel on both of my Mustangs changed considerably.
I’m on 9 years with the lines on my Boss.
I don’t disagree for my application or for a serious enthusiast. But for a casual user, I certainly wouldn’t call them “inadequate”. Lots of tires or brake pads are inadequate for track use, much like a set of cheap NAPA budget pads are inadequate - they will fail. But OEM rubber lines are fine. I’d consider stainless braided lines as a performance upgrade.

The real answers I’m hoping to draw out of the experienced crowd here at TMO is “How long before replacement?” for some of these components.
 

JDee

Ancient Racer
1,517
1,545
Exp. Type
W2W Racing
Exp. Level
20+ Years
halfway between Mosport and Shannonville
I first learned about aeroquip brake lines back in the early 60s when I was about 9 years old. A group of guys my dad hung with were building formula cars which won many championships and still run today in FF regional and historics. They were fastidious about details, and aeroquip lines were considered essential. Mostly it was to protect from flying junk taking out a rubber line as rubber lines back then were pretty crummy, but they also gave a much firmer pedal when things got hot.
Not sure how much risk there is of flying junk in a sedan, or if OEM rubber lines these days are a lot better and stronger, but just because it has always been de rigueur in racing to have aeroquip brake lines, I did it.
Or is it just monkey see monkey do? I dunno.
 
1,118
1,086
In the V6L
I don’t disagree for my application or for a serious enthusiast. But for a casual user, I certainly wouldn’t call them “inadequate”. Lots of tires or brake pads are inadequate for track use, much like a set of cheap NAPA budget pads are inadequate - they will fail. But OEM rubber lines are fine. I’d consider stainless braided lines as a performance upgrade.

The real answers I’m hoping to draw out of the experienced crowd here at TMO is “How long before replacement?” for some of these components.
Inspect, inspect and inspect. Any sign of wear, damage or cracking, replace. That goes for everything from bushings to brake lines to wiring harness.
I first learned about aeroquip brake lines back in the early 60s when I was about 9 years old. A group of guys my dad hung with were building formula cars which won many championships and still run today in FF regional and historics. They were fastidious about details, and aeroquip lines were considered essential. Mostly it was to protect from flying junk taking out a rubber line as rubber lines back then were pretty crummy, but they also gave a much firmer pedal when things got hot.
Not sure how much risk there is of flying junk in a sedan, or if OEM rubber lines these days are a lot better and stronger, but just because it has always been de rigueur in racing to have aeroquip brake lines, I did it.
Or is it just monkey see monkey do? I dunno.
I've used a number of brands of stainless lines in the last 15 years. Once I figured out that Ford OEM lines were as good as they were, I changed my approach when installing other people's calipers, retaining as much OEM as I can, using stainless where I need to extend. Stainless only goes in places where the two ends don't move relative to each other. Works great for what I want.
 

Duane Black

Curbs go brrrppp
492
322
Exp. Type
Time Attack
Exp. Level
5-10 Years
Durham, NC
I replace brake calipers and front wheel hubs each season. I replace tie rods every other season. I change oil every other event, and flush my transmission and differential yearly as well. I go through a few air filters a year.
 

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