Will this modification affect vehicle legality or safety?
Documented on the Ford Mustang build
Published February 26, 2026
Modifying fender wells to clear larger tires can affect splash protection and may be subject to local vehicle regulations.
Full Answer
Modifying fender wells to clear larger tires can affect splash protection and may be subject to local vehicle regulations. Ensure that tires do not protrude illegally and that the tubs are structurally sound and sealed to prevent debris from entering the cabin or suspension areas.
Documented In This Build
Related Knowledge
What welding technique is recommended?Do I need to use preformed tubs or can I fabricate from sheet metal?How much clearance should I allow for larger wheels/tires?How should I protect the new metal from rust?How do I prevent warping when welding thin sheet metal?What wheel/tire sizes can this modification accommodate?How much extra tire/wheel clearance can I expect?How difficult is this for someone with limited metalworking experience?
Related Parts
MIG welding wire (ER70S-6, 0.030-0.035" spool)
$30
Grinding / flap discs (pack)
$20
18 gauge cold-rolled steel sheet (for tubs)
$60
Preformed wheel tubs (alternative)
$250
Seam sealer / panel adhesive
$10
Weld-through primer / zinc-rich primer
$25
Automotive body filler (Bondo or equivalent)
$15
Self-tapping screws / rivets & nutserts (fasteners)
$10
Related Tools
Hammer and dolly set
Spot weld cutter / drill
Angle grinderDeWalt DWE402
Sheet metal brake / metal folderEastwood Leaf Break (or equivalent)
Measuring tools and markers (tape, scribe, straightedge)
Clamps and cleco fasteners
MIG welderLincoln Electric LN-140 (or equivalent)
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