Cracked rim repair is the most safety-critical job a wheel shop does. A crack lets air out, and if it grows the wheel can fail under load. Many cracks in the inner barrel or lip can be TIG welded with aluminium filler, machined smooth and leak tested, and the wheel goes back into service. Others should never be welded. This page explains how crack repair works, where good repairers draw the line, and what to ask before you agree to a weld.
How to tell your rim is cracked
The usual first sign is a tyre that keeps losing pressure with no puncture found. A fitment centre may spray soapy water on the wheel and see bubbles from the barrel rather than the tread or valve. Cracks are often on the inner lip, behind the spokes, where you cannot see them from outside, and many start from an old bend that was never fixed, or from a bend that was straightened too hard. If a shop finds a crack during a bent rim repair, that changes the job and the price.
How a crack is welded and tested
- The tyre comes off and the area is cleaned back to bright metal.
- The crack is ground out into a groove and often drilled at each end to stop it running further.
- It is TIG welded with an aluminium filler rod suited to wheel alloy.
- The weld is ground and machined flush, especially where the tyre bead seats.
- The wheel is leak tested, either in a water tank or with soapy water under pressure.
- The area is refinished, then the tyre is refitted and the wheel balanced.
Cracks repairers refuse to weld
Welding changes the metal around it, so careful repairers only weld where the load and risk allow. Most refuse, and advise a replacement, when the crack is:
- in a spoke or where a spoke meets the barrel;
- near the wheel bolt holes or the hub, which carry the weight and braking forces;
- on a wheel that has been welded before;
- long, branching, or across the full width of the barrel.
If a shop is happy to weld any of these, get a second opinion. Buying a replacement or a sound second-hand mag wheel is cheaper than what can go wrong.
What to ask before you agree to a weld
Ask where exactly the crack is and send photos of the back of the wheel. Ask whether they drill the crack ends, what filler they use, how they test for leaks, and whether they check the wheel for runout while it is on the machine. Ask what warranty they give on the weld. And when you sell the car, tell the buyer the wheel has been welded; it is the honest thing to do and many buyers check.
What to put in your request
- Where the crack is: lip, barrel or spoke
- Photos of the back of the wheel, close up
- Wheel size and finish
- Whether the wheel was welded or straightened before
- Whether you want a replacement quote as well
Cracked Rim Repair for drivers, fleets and workshops
- Private car owners: a slow leak traced to a hairline crack in the inner barrel
- Enthusiasts, 4x4 and performance drivers: a cracked aftermarket wheel that is no longer made, welded if it can be
- Company and rental fleets: cracked wheels on pool cars assessed and replaced where welding is unsafe
- Dealers, panel shops and insurers: a cracked wheel found on a trade-in, welded or swapped before sale
- Tyre shops and wheel workshops: fitment centres sending leaking wheels to a shop with a TIG welder
- Truck, bus and taxi operators: cracked rims on shuttle vans checked for repair or replacement
- Farms: cracked bakkie and trailer rims from rocky farm tracks, mostly replaced
- Mines and construction sites: cracked site vehicle wheels condemned or replaced for safety
Frequently asked questions
Is a welded rim safe to drive on?
Can a crack be fixed with sealant or glue?
Can steel rims be welded too?
Do you weld cracked rims?
Cracked Rim Repair by province and city
- Johannesburg
- Pretoria
- Centurion
- Midrand
- Sandton
- Randburg
- Roodepoort
- Krugersdorp
- Randfontein
- Germiston
- Boksburg
- Benoni
- Kempton Park
- Alberton
- Vanderbijlpark
- Vereeniging
- Durban
- Pinetown
- Pietermaritzburg
- Richards Bay
- Newcastle
- Ladysmith
- Gqeberha (Port Elizabeth)
- East London
- Kariega (Uitenhage)
- Mthatha
- Cape Town
- Bellville
- Paarl
- Stellenbosch
- George
- Worcester
- eMalahleni (Witbank)
- Middelburg
- Secunda
- Mbombela (Nelspruit)
- Rustenburg
- Brits
- Klerksdorp
- Potchefstroom
- Mahikeng
- Polokwane
- Tzaneen
- Kimberley
- Upington
- Bloemfontein
- Welkom
- Sasolburg