Hi there - I know that this topic has been addressed several times already, but I was unable to find a satisfactory answer.

I have a 97 4Runner SR5 that I bought used. It came with rear airbags and shortly after purchasing it, I installed Billstein shocks front and rear.

The rear end is sagging substantially and it's driving me nuts.

What causes this? I may have a slow leak in my airbags - could that cause this?

Are my coils worn out? Do I even have coils in the back if I have airbags?

Thanks for your help!

 

someone may have been using it for a tow rig-hence the air bags-or simply to raise a saggy butt.it does have coils.number of manufacturer to either raise or at least get it back to stock with new springs or spacers.or fix the leak in the air bags

 

Are coils and springs the same thing? Is there anything wrong with having "flat" airbags?

If I end up replacing my coils/springs, what brand/model should I consider?

 

Yeah, it sounds like the previous owner may have used it for towing. The airbags were an add-on to help support the extra weight. Regardless, even if the bags were leaking, the rear shouldn't be sagging. If it is, you just have a bad set of coil springs. You can just get a new set of coil springs from toyota for cheap or there are various upgrades you can make to your suspension system. A set of PP springs will solve your problem without a doubt and give you about an inch of lift. Do a search on Old Man Emu (OME) and/or PP springs.

Hope this helps

 

hey thanks for the info - will I need to replace all 4 coil springs or just the rear?

Will the airbags be damaged if they are flat and I don't keep them filled?

Thanks

 

You could just replace the rear, again I would suggest a set of PP springs. They will give you a little stiffer ride in the rear but it will most defin. fix your sagging problem. I believe you can get a set from Performance Products for $150. If you just replace the rear, you may have a slight rake to it. By that I mean the rear will sit a little higher than the front.

It depends on the airbags, I run an airlift 1000 on mine and they recommend no less than 5 psi in them. However, if there is a leak or they are flat...what would it matter if they were damaged? You don't need them if you aren't hauling anything and even if you are...the PP springs should take care of the sag as again they are pretty stiff. Is there an on-board air system on the vehicle that automatically fills the bags at a set interval?

 

i have a set of 98 coils that i would sell for a very very reasonable price if you want them. definitely no sagging in the rear when i took them out!

 

I would suggest the OEM 4x4 coils off a 99. i think it will give you a 1" lift comparitive to the stock height. most any other choice aftermarket you will have to look into a lift.

 

If you ran the airbags with little or no air in them they may have a pinch hole or crease that leaks air. Also check all the lines to make sure on of the air lines didn't come loose and you lost all your pressure. Have you tried putting any air in the bags via the schraeder valve? Do they hold pressure?

If the rear is sagging then you likely also need some new springs. Your truck should have an original ride height of about 35" from fender to ground, both front and back. There are many options to restore or increase the ride height, but the most common are replace with just new OEM springs for your truck, OEM springs from a 99 4WD 4runner (supposedly about 1" of lift.....although ShiftMX had an issue on his 01 4runner getting the proper lift......not sure what exactly the deal is there), Performance Products springs (about 1.5-2" of lift) or Old Man Emu (OME) 906 springs (about 1.5-1.75" lift). I have the OME springs all around so I am obviously biased a bit towards the last option.

 

A quick question. Did it sag before you put on the Bilsteins?

The reason I ask is that I have noticed others getting the front to sit a bit higher than the rear after going with Bilsteins. When I added mine I felt I got a slight rake too and during installation I felt that the new front strut allowed the spring/coil to stretch more than on the stock strut upon installation.

As others have said, try see in the airbags hold air. Heck adding some air might solve your rake (unless you installed the spring cup on the strut the wrong way!)

 

Dude take it in to toyota, have them run the vin and check for recalls. If your piece falls under recall like mine. You will get brand new coils in the rear. Rip thoes air bags out while your down there too. It dosent sound like you tow much. If your truck dosent fall under recall. PM me and I have a set of brand new coils for a 98. I mean brand new, they still have the stickers on them.