How do I lower the spare tire without the factory 2004 Isuzu Asce

Either buy a used tool from a salvage yard, or use a socket and ratchet. You should be able to find a socket or extension that will fit the post in the floor to lower the tire.

Before doing anything make sure you have air in your spare..,A good Jack and spare tire removal kit....The kit should be under or behind the passenger seat..I don't like the factory Jack it comes with because sometimes you need a good strong block of wood to achieve the height you need to contact the vehicle..and sometimes they don't work correctly...Some spare tire release tools are under the hood..It is a long skinny rod ...You have to use rod or rod kit to stick through the rear bumper at the slot and turn the rod counterclockwise after you feel the rod connect with the release mechanism..,Lower the spare until it touches the ground then keep turning so you can have enough slack to remove cable from spare tire...Set parking brake while in park and use the lug nut removal tool to break loose the lug nuts before raising vehicle..They are removed counter clockwise..Don't take nuts off just break them loose...Block front wheels for safety with anything solid you can find if you are stranded..If you can't find anything rely on parking brake..It should be safe in park but safety first....Jack vehicle up..,remove all lug nuts put them in a safe clean place don't lose them..Remove flat tire..Install spare..Start each lug nut and tighten them all tight by hand..Snug each nut clockwise in a star pattern ..Get them good and tight but don't try to hurt yourself or break the stud...Lower vehicle,remove Jack..Snug each lug nut once again for safety..Put flat in truck bed for now rather than back in the spare storage area because it has to be repaired..Crank spare cable that held spare under truck clockwise until it stops.Remove tool..,Gather all tools used., remove blocks from front tires.,Head to a tire store...

Loosen lugs first. Chock opposite front wheel. Put emerengcy brake on. Jack up vehicle where the rear spring meets with the frame. Raise vehicle about 1 inch swap tires. Install lugs snug. Lower vehicle till tire just touches the ground then tighten lugs. Finish lowering the jack and remove chock place both in vehicle.
Start truck, release jack and continue on your way. Make sure spare has proper amount of air. If not go to gas station and fill tire. If low on air do not go over 30 mph. Hope this helps.

When you look at the shaft if you see a large slot then any jack handle with a pin through the shaft or a loop on the end will do the job.

look for a hole in bumper possibly aroun tag area. or could be just above bumper

Rotate the hoist shaft counterclockwise in order to lower the spare tire to the ground. Continue to rotate the shaft until the spare tire can be pulled out from under the vehicle and removed. If the spare tire does not lower to the ground, the secondary latch is engaged causing the tire not to lower.

If the secondary latch is engaged and the cable end is visible, perform the following procedure: 3.1. Tighten the cable by rotating the hoist shaft clockwise until you hear 2 clicks or feel it skip twice. You cannot overtighten the cable. 3.2. Loosen the cable by rotating the hoist shaft counterclockwise 3 or 4 turns. 3.3. If the spare tire can be lowered, repeat steps 1 and 2 to see if the spare tire can be removed. 3.4. If the spare tire cannot be lowered, rotate the hoist shaft counterclockwise until approximately 15 cm (6 in) of cable is exposed. 3.5. Raise and support the vehicle. 3.6. Place a transmission jack, or equivalent, under the spare tire. 3.7. Position the center of the transmission jack under the secondary latch release button at the center of the spare tire. Arrange the arms of the transmission jack so they will support the tire after it has been released. 3.8. Raise the jack until the spare tire stops moving upward and is firmly held in place, releasing the secondary latch. 3.9. Lower the tire. If the spare tire is hanging by the cable, rotate the hoist shaft counterclockwise until the tire is low enough to remove.

It is a crank and it is the same tool used to raise and lower your jack,it might be were your jack is stored.

If the spare tire does not lower to the ground,the secondary latch is engaged
causing the tire not to lower Your vehicle has an underbody-mounted tire hoist
assembly equipped with a secondary latch system.It is designed to stop the spare
tire from suddenly falling off your vehicle if the cable holding the spare tire
is damaged.For the secondary latch to work,the tire must be stored with the
valve stem pointing up.
1.Check under the vehicle to see if the cable is visible.If it is not visible
proceed to Step 6.
2.If visible,first try to tighten the cable by turning the wheel wrench clockwise
until you hear two clicks or feel it skip twice.You cannot overtighten the cable.
3.Loosen the cable by turning the wheel wrench counterclockwise three or four turns.
4.Repeat this procedure at least two times.If the spare tire lowers to the ground
continue with Step 2 of removing the Spare.
5.Turn the wrench counterclockwise until approximately 6 inches (15 cm) of cable is
exposed.
6.Attach the jack handle,extension and the wheel wrench to the jack and place it under
the vehicle towards the front of the rear bumper.Position the center lift point of the
jack under the center of the spare tire.
7.Turn the wrench clockwise to raise the jack until it lifts the end fitting.
8.Continue raising the jack until the spare tire stops moving upward and is held firmly
in place.
9.Lower the jack by turning the wheel wrench counterclockwise.Keep lowering the jack
until the spare tire slides off the jack or is hanging by the cable.
10.Disconnect the jack handle from the jack and carefully remove the jack.Use one hand
to push against the spare while firmly pulling the jack out from under the spare tire
with the other hand.

First off did you Know this ?????

Make / Models : Model/Build Years:
GMC / 1500 2004
Regency / Chevrolet 1500 2004
MANUFACTURER: General Motors Corp.
NHTSA CAMPAIGN ID Number : 04V240000 Recall Date : MAY 14, 2004
COMPONENT: Tires: Temporary/Emergency Spare Tire
Potential Number Of Units Affected : 285
SUMMARY:
The spare tire and wheel assembly that was provided on certain conversion vehicles will not fit on the front wheel hub due to offset of the wheel. However, it will fit on the rear wheels.
CONSEQUENCE:
If someone has a flat tire on the front wheel, they will not be able to install the provided spare tire.
REMEDY:
Dealers will install a spare wheel with the correct offset. Owner notification began on June 11, 2004. Owners should contact Regency at 1-800-989-4727.
NOTES:
Customers can also contact The National Highway Traffic Safety Administration's Auto Safety Hotline at 1-888-DASH-2-DOT (1-888-327-4236)

SPARE TIRE is Under rear of truck use Long Cranking in HoleClose to Lisence Plate to Lower it Down Cranking Counter Clockwise. Wing in center of Wheel pokes thrugh Hole in Center of wheel
Reverse Procedure to Put old tire in Tire Storage Compartment

1. Locate Jack & Wheel Lug Nut Wrench
2. There is Directions as to where to placse the Jack for raising Truck Where Jack is Located
3. Set Park Brake Chalk tire if possible & Hazard lights (If on the Roadside)
4. Loosen all Wheel Nuts on said wheel before Raising Vehicle
5. Place Jack In Recomended Placment spot
6. Rear is Normaly on Axel close to Shock
7. Front is Normaly on FRAMERAIL
8. Raise vehicle untill tire is 3-4 inches off ground as Flat will Lower vehicle
9. Remove All Wheel Nuts And Wheel
10. Place new wheel/tire on Vehicle and start all nuts
11. Tighten nuts as tight as Possible then Lower Vehicle Untill tire touches ground Good
12. Now Toque Wheel Nuts as tight as Possible with hand tool
13. Lower vehicle all the way down
14. Put away tools and Reliece Park Brake
15. Torque should be around 100-130 foot Pounds

I Hope this is What You Wanted Its Off the Cuff as My Reference Books done have this Procedure.

The spare is held in place by a cable that is cranked up and down with a tool that is stored with the jack, the access hole for the tool to crank the spare down is in the rear bumper in most trucks, look underneath to see it and be sure.