I have a 2006 chevy trailblazer ls.the door sticker says 30 psi in the front and 35 psi in the back.is it ok to run 35 psi all around?
No, just go with the 30/35.
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I have to agree with old_mopar_guy.
Chances are going to 35 F&R would have a negative affect on vehicle handling, most likely understeer versus oversteer.
I’ve owned three of these of various model years. Aside from potential adverse performance issues, you probably won’t like the ride much with 35 psi in the fronts. Tried that once, was way too harsh for me. I usually bump them up a bit to 32 and run 35 in the back. 30 psi is a bit too mushy for me…
What more do you need to know . I think the people who built this thing might know best.
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beyond the above advice, I would double check the door sticker to make sure that the tires/wheels haven’t been swapped to a different size sometime over the last 13 years. The psi on the door sticker is for the tire size that is also listed on the door sticker.
Not everyone changes tires sizes, but a lot of folks do.
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35 all the way around is fine .Thats what I run on my Ascender which is Trailblazer they made for Isuzu . Running 30 in the front would cause the Tpms to go off if it was only a couple pounds low . There is no difference in the way it drives other than the ride is slightly stiffer .
Increasing the fronts would decrease understeer, AKA plowing.
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Sorry, but You contradicting Yourself. Plowing - in my world - would be massive understeer. That doesn’t fit with decrease. I take it, that you meant it the other way around. 
In that case, You’re right, but it could end up with the OP’s rear end, ends up with a “slip slidin` away”.
understeer=plowing
Increasing front tire pressure would decrease understeer. Since this is a nose-heavy vehicle, it would still understeer, just less. It would not get to the point of oversteer.
Remember that tire psi is determined by the weight of a vehicle. It is like a trial and error to get the perfect pressure for your tires. I run 34 psi on my nitto tires and it seems pretty fine.
That’s only one factor. The tire PSI is determined by the carmaker after all their design and testing work. The owners manual will say if there are conditions when the normal PSI should be modified temporarily.
For the record:
On every car I overinflated the front tires on, the steering became more responsive, and for me, borderline twitchy.
Sounds like oversteer to me.
Overinflated steer tires = Oversteer
Underinflated steer tires = Understeer
Been common knowledge since ol’ Henry opened a car factory.
Are planning to resurrect every old tire-related post? That’s considered bad etiquette in this forum.
Your explanation is a bit oversimplified, by the way.
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Better than clogging up CarTalk’s servers by starting ten useless new threads on the subject, lol!
No such thing as an “old thread”, if it contains good information, or could use some fresh insight.
Steering response is a separate thing from over/under steering.
My 1975 Civic steered like a go cart, but still reliably understeered unless you let off the gas in the middle of a hard turn.
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