Is it possible raise the suspension without the engine running.engine siezed

very possible as oil is what is used so that engines do not seize
pull it down and check for rings and badly scored bore

a bit of this & that; probaly need a jack (raise engine relative to body/firewall or opposite that) and an assortment of socket extensions, swivel joint & patience. Do it w/ engine cold & use a little 'never sieze' on new plugs. It is possible, just not convenient.

If I read right you just want to raise the air suspension and solenoid valves jumper the air compressor and it will fill the airbags

A few possibilities with front end noise. Possible worn shock bushings or suspension bushings. As a car accelerates or slows down, the front suspension raises or lowers, thus causing movement of front end components.

Park vehicle on level surface, set the parking brake and chock the rear wheels. Disconnect negative battery cable and raise vehicle up and support it with jack stands. If equipped with air suspension disconnect electrical power to air suspension.Position jack underneath of engine oil pan, use piece of 2 x 4 or block of wood and raise engine slightly to take the weight of engine from motor mount. Inspect the engine mounts for crack or rubber deterioration and separation.

1994-96 VEHICLES
( see Figures 6 and 7 / click image for zoom )

Fig. 6: Oil pan mounting bolt locations-1996 3.1L engine shown

Fig. 7: Oil pan sealant application points-1996 3.1L engine shown

1. Disconnect the negative battery cable.
   

It may be necessary to remove the hood, with the help of an assistant, for access.

1. Remove the engine mount strut and A/C compressor (if equipped) and the engine mount strut bracket assemblies.
   
2. Remove the electric cooling fan assemblies. -28467 and J 26462, or equivalent.
   
3. Raise and safely support the vehicle. Drain the engine oil.
   
4. Remove the front exhaust manifold pipe.
   
5. Remove the intermediate shaft bolt/screw.
   
6. Remove the oil level sensor.
   
7. Remove the engine splash shield.
   
8. Suitable support the drivetrain and front suspension with jack stands.
   
9. Remove the transaxle mount side frame retaining nuts from the drivetrain and suspension frame assembly.
   
10. Remove the engine mount side frame nuts from the drivetrain and suspension frame assembly.
    
11. Unfasten the rear drivetrain and front suspension frame bolts/screws.
    
12. If equipped, remove the lower drivetrain and front suspension frame bolts/screws.
    
13. Remove the engine mount assembly.
    
14. Remove the flywheel inspection cover.
    
15. Remove the starter.
    
16. Disconnect the transaxle mount assembly from the oil pan.
    
17. Unfasten the side bolts and screws and the retaining bolts and screws, then remove the oil pan. Remove and discard the oil pan gasket.

To install:

1. Clean the gasket mating surfaces.
   
2. Apply a small amount of sealer on either side of the rear main bearing cap, where the seal surface on the cap meets the cylinder block. Install a new gasket on the oil pan.
   
3. Position the oil pan and secure with the retaining bolts and screws. Tighten the retaining bolts and screws to 18 ft. lbs. (25 Nm) and the side bolts/screws using tool J 39505 or equivalent.
   
4. Fasten the transaxle mount assembly to the oil pan.
   
5. Install the starter motor.
   
6. Install the flywheel inspection cover.
   
7. Install the engine mount assembly.
   
8. Carefully raise the drivetrain and front suspension assembly. Install the rear drivetrain and front suspension frame bolts/screws.
   
9. Fasten the engine mount frame side nuts to the drivetrain and front suspension frame assembly. Install the transaxle mount frame side nuts to the drivetrain and suspension frame assembly.
   
10. Remove the jackstands from the drivetrain and front suspension frame assembly.
    
11. Install the engine splash shield and the oil level sensor.
    
12. Install the intermediate steering shaft bolt/screw. Connect the front exhaust manifold pipe.
    
13. Carefully lower the vehicle.
    
14. Remove the engine support tools.
    
15. Install the electric cooling fan assemblies.
    
16. Install the engine mount strut and A/C compressor, bracket and the engine mount strut bracket.
    
17. If removed, install the hood assembly.
    
18. Fill the crankcase to the correct level. Connect the negative battery cable. Run the engine to normal operating temperature and check for leaks.

Hope this helps (remember to rate this answer).

The compressor should only run until the rear suspension reaches the desired height. If it continues to run after the suspension has raised to ride height then you may have a leaking air bag/solenoid or line. If you dont have any leaks it is possible the EVO(air suspension module} or relay is at fault.

It is an air suspension system. If it keeps giving you problems try connecting a switch in between the "hot" wire that comes from the battery.

31x10.50r15s will rub the front fender while turning if you dont install either a suspension or body lift. Adding a leaf spring to the rear will not neccessarily raise the vehicle you must add a block to the spring seat to raise the height. However you can use 30x9.50r15 without any modification. Hope that answers your question.

You will have to remove your engine. You still will not have enough room to remove the pan from you big block by just trying to raise it.