I have a 91 Z28 T-Top car with 162,900 miles on it. I bought it in December of 2009 and have put about 10,000 miles on the car since I've had it. It used to be my daily driver but I have another car now so it sees maybe 200 miles a month at most right now.

I'm fairly new to cars so excuse me if this is a stupid question. Since our cars are unibody, I've always been pretty paranoid about frame damage. It seems like the cars are so fragile and that worries me because I'd like to keep my car as long as possible. I'm 19 and I don't really ever plan to get rid of it.

So now to my question: will putting a lot of miles on my car eventually cause frame damage? Say if I at some point hit 300k miles, will the stresses from all of those miles cause the frame to weaken or cause the welds hold the car together to break? As I said earlier, I don't ever want to have to sell this car or get a new if at all possible, and I love to drive it. But I sometimes have to wonder if I should try to limit the miles I put on it so that I won't have to scrap it at some point. My car does have a wonderbar on it but it won't have sub frame connectors on it probably for another 3-4 years (I'm still in college and don't have the income to spend on things unless it is absolutely required to run).

 

just dont put 500hp in without sfcs and don't wreck it and the only damage will be rust

 

I've never heard of one just falling apart like that... sfcs should have been factory from what I understand. If you have access to a welder you could just make your own

 

Nothing to seriously trouble yourself about.

Have the SFC's installed as soon as time and money dictate.

JamesC

 

I'd bet daily driving a bone stock car puts far more strain on it's chassis than doing something like drag racing with a 500+HP engine.

The whole "these cars are fragile!" thing is BS as far as I'm concerned. My old car had like 200,000 miles on it and hundreds of hard-hooking drag strip launches without ever having any sort of sub-frame re-enforcements. It never showed any signs of stress any where.

To the OP, just keep your car clean of stuff like road salt and it'll last forever. Rust and collisions are what'll kill your car.

 

This is what I was hoping to hear! Since I live in Oregon road salt never gets used. If it does snow they only put down gravel usually. If it did snow I wouldn't drive my car anyways so it wouldn't matter much.

 

[QUOTE=88IROC350TPI;5199103]I'd bet daily driving a bone stock car puts far more strain on it's chassis than doing something like drag racing with a 500+HP engine./QUOTE]
Is this serious? I can't tell

 

[QUOTE=keeslinger31;5199303]You think regular driving isn't rough on your chassis? Think of how often it's twisting, vibrating, and flexing under normal circumstances... Pot holes, bumpy roads, uneven roads, think of all the moisture and grime such a car sees...

Now think of a drag race that twists the chassis once upon launch and continues down a perfectly straight and smooth road for a 1/4 mile or less.

 

Think of the balance of those forces. On the street you will not get as much traction if you were to choose to launch the car. But on the strip the road is perfectly smooth and very
sticky, you get max traction for that 4500rpm launch, your tires stick the 10 bolt moans and off you go the twisting forces of 500ftlbs going through the rearend lifting on the body
in one spot and pushing it down with tremendous force ( note the 500ftlbs )
Now a bump will simply be absorbed by the shocks and springs and the leftover energy will be transferred to the chassis via strut towers and then absorbed with little or no bending
unless you hit a ditch or comparable pot hole.
I don't see street driving to be worse on the chassis then drag racing on the strip... but im a complete idiot and ive never seen a car in my life let alone raced one

 

Potholes are brutal on suspension parts... not so sure they're as harsh on the chassis as hard launches.

I wouldnt stress over it, but these cars do show signs of fatigue. If you've got a hardtop car you probably The Crack at the back corner of one or both of your side windows. T-Top cars dont put all that force into the same corner due to the roof construction, but that energy has to be dissipated somewhere...

And that's why i have sfc's. I dont worry about much as far as chassis integrity as long as the car isnt rusty.

 

What if you have rot in the subframe?