So my left rear tire looks flat. I checked the pressure and it was at 13 psi. i filled the tire with air and did nothing. so i replaced the tire with the full size spare and my original tire was perfectly fine. In fact, it is close to max pressure because of the extra air i put in. After putting on the spare, it too looks flat just like the original one did. Looks a little deflated on the bottom so i'm guessing i have a shock that is out or needs to be recharged or something? Possibly my sub box and the miscellaneous stuff in the back is finally showing it's effect on weight? I'm assuming the former. If i need to replace something, what do i need and where is a good website to go who can order directly from an OEM Chevy manufacturing plant? I have a 98 LT with the premium ride suspension equipped. Thanks pros!

 

Do you have the auto-leveling suspension? If so then a good pair of air shocks is all you need.

 

I really don't know but i'm assuming i don't just because i don't see anything that tells me i do. Also, I have the original invoice of the blazer and it says "touring suspension replacing premium suspension" with no charge so i'm also guessing touring is the one i have and not premium. Either way, do I just need to replace the shock(s) for the type of suspension equipped?

 

Take a look at teh shocks, do you see oil on them, are they bolted in place?
Oil means it ahs a leak.
Its not uncommon for the spare tire to be low on air too. It typically never gets checked during routine maintenance. Check your psi, fill it up, and check it agian 8 hours later. You could just have a flat tire and the spare is low due to lack of amintenance.

 

To find out you can look at the label in the glovebox for G67 it indicates the Automatic Leveling System and it uses air shocks and an air compressor located in the back to adjust the shocks to the proper level. If the lines have a leak then one or both shocks could not be working properly, it is usual for an air shock to have leaking lines and then have problems...

With a regular shock system you would have to do like Hanr3 suggests to crawl under the car and look at the shock for an oil leak, if no leak then you could have the nitrogen gas fouled and no longer providing the oil the ability to reduce foaming...

 

Considering the fact that an air suspension uses one pump, this should not result in one shock providing more support than another. If the line breaks, they both go down. The only shock issue that could cause this would be for the shock to lock up. A shock in and of itself does not add spring rate to the suspension when at rest (unless it is a coil over load assist such as what I have installed on the back end of my truck).

My question is, how can a tire have 13psi when on the truck, but read full when not on the truck? How do the other tires on the truck read, pressure wise and how do they look?

 

For the sagging sidewalls... some tires just do that naturally... especially when they get older... How's the other side look?

Also, like Hanr said, check the spare's PSI (which reminds me to do that tomorrow... even though I can't use it...)

 

With radial tires you cannot use their appearance to estimate air pressure. If it has proper air pressure, then it's OK unless there's a physical problem with the tire. Use a good quality gauge and check carefully.

If the vehicle tilts to one side, look for broken springs.

 

thanks for all the replies. I do not believe that a shock is the problem as it would not cause this problem at rest as mentioned. both spare and original tire for left rear had a reading of 12-14 psi while on the vehicle, right front was at 38, others are at 34 so it isn't the gauge and left rear is only tire/area in question. the tires i have, dunlop radial rover rvt all terrain, were bought an installed brand new in november 06. Checking the original tire's pressure while not on the vehicle it was the same, around 14 psi. sorry about that, but that sucker felt really full of airwhen i took it off the rim so i assumed it was close to max.all 4 look great and there are no signs of leaks on any of them. the spare was pretty dusty/dirty, clearly hasn't been used in a while assuming it was ever used at all. The vehicle looks normal as it always has in terms of height; you can't clearly see that one side is off from the other, looks the same. The ride doesn't seem affected while driving around. I am going to take measurements this afternoon with the spare on. i will also try toget time to putthe original tire back on and get measurements and readings.

 

I measured from the ground to the fender and the difference was only 2 cm so i tried adding more air to the spare (still on vehicle) and i got the pressure to 30 psi and doesn't have that deflated look on the bottom anymore so it's merely a tire issue and not suspension. Thank you for all of your assistance, been a very very solid blazer so far.