Jeep Gas Skid Modification (Free Ground Clearance)

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Jeep Gas Skid Modification

CONTENTS

1) Vehicle Setup
2) Peformance Review
3) Modification Write-up



1) VEHICLE SETUP

A 1" body lift needs to be install prior to this modification



2) PERFORMANCE REVIEW

The stock HD skid plates found on some TJ Jeeps provide sufficient strength for general trail riding with the thicker steel, full coverage on 5 sides, and reinforcing ribbing. But it hangs down a fair amount (Fig 1). By utilizing the gap created between the chassis and body created with the installation of a 1" body lift, the stock gas tank and skid can be tucked up for increased ground clearance for essentially free. This improves the departure angle and reduces the number of times the tail end scrapes coming off a ledge or over a rock.

Fig 1. Stock gas tank skid plate hangs a bit low

3) MODIFICATION WRITE-UP

Preparation:
Depressurize the fuel system by removing the fuel pump relay (Fig 2) and crank over the engine for a few seconds. Replace the relay and disconnect the ground from the battery for safety. Jack up the rear end and set on jack stand, remove driver's side tire for better access to tank connections (Fig 3 and 6).

Fig 2. Removing the fuel pump relay from the PDC for fuel system depresurization



Fig 3. Set rear axle on jacks stand, remove driver's side tire for better access to tank

Disconnecting Fuel Tank:
Remove 8 screws securing filler cap bezel to body and filler tube. Replace gas cap to keep dirt out of filler tube (Fig 4). Reach into fender cavity and snip zip tie holding axle breather tube to filler tube (Fig 5).

Fig 4. Remove 8 screws holding fuel bezel to body and tank filler tube.



Fig 5. Cut zip tie holding vent hose to fuel filler tubes.

Disconnect wiring harness, fuel line, and evap line from gas tank (Fig 6 & 7). Wiring harness plug - slide red clip down, then squeeze button on chassis-side of the connector and unplug. Fuel line - squeeze ears together and gently work fuel line connector apart. Evap line - simply twist off the rubber hose.

Fig 6. With driver's rear tire removed, access to fuel tank
connections is MUCH easier.



Fig 7. Make necessary disconnections to fuel, wiring harness, and evap lines.

Tank Removal:
Support gas tank/skid with a floor jack. Remove the 7 skid plate nuts (3 front, 4 rear). Gently and slowly lower gas tank/skid. It may help to tilt tank to the passenger side to slip out the fuel filler tubes on the driver's side. Unbolt the straps and lift the plastic fuel tank from steel skid plate (Fig 8). Clean out any dirt that accumulated in the skid (Fig 9).

Fig 8. Fuel tank and skid plate removed from Jeep and separated.



Fig 9. Some dirt found in the bottom of the skid plate.

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Modifying Skid Plate:
Cut mounting flanges off steel skid plate (Fig 10). Allow for sufficient overlap of metal when planning the cuts, typically, right at the main tank level is good but preserve the strap mount slots on the front.

Fig 10. Cut the three mounting flanges from the main skid plate body.

Grind off paint from area to be welded. Over lap the mounting flanges 1" lower on the skid plate and clam into place (Fig 11). Stich weld back together (Fig 12). Alternatively, you can clamp, drill, and bolt these pieces together. Bend the front of the skid plate between the mounting flanges inward slightly for a hair more track bar clearance (Fig 13).

If the straps need to be lengthened, cut and weld in a piece of thin steel or elongate the front strap slots. Clean up all welds and hit with some spray paint.

Fig 11. Re-align flanges 1" lower and clamp into place.



Fig 12. Stitch weld (or bolt) the flanges back onto the skid plate body.



Fig 13. Trim excess steel and bend for greater track bar clearance.

Reinstall Skid Plate:
Reinstall gas tank and modified skid plate in the reverse order of removal. Having an assistant helps a great deal. For those with a rotated pinion the clearance to the track bar will be tight (Fig 14) but can be improved with the techniques here. The rear shock is also tight for shocks with a rigid dust sheild (Fig 15).

The stock skid is now tucked up 1" further (Fig 16) for additional departure angle improvement. Note the before and after difference (Fig 17).

Fig 14. Tight track bar fit but more clearance that I previously had.



Fig 15. Tight driver's side shock clearance due to steel outer dust
sleeve on shock. Most shocks don't have such as sleeve and would
have more clearance.



Fig 16. Modification finished and trail tested. Very good.



Fig 17. Before and after comparison.

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