Running 30 inch or bigger tyres? got a front locker or just drive it hard?
Sooner or later (or every weekend) you'll be breaking  front CV's.
They're your stock sierra's weakest point.
There's two ways the stock units break. Either the axles let go, or the CV joints expand or deform enough to break the bell.
Fitting rings over the  bell helps, but not much. The ultimate answer is stronger CV's and axles.

Cro moly is a much stronger material than the standard steel used. Our CV's are bigger than standard- in fact the very biggest that'll fit in the housing.

The axles are not only made from stronger cro moly versus the standrd steel units, but they are thicker- so even stronger again.

Standard front axles and CV's are 22 spline. These are 26 spline units (same as a rear ) so you'll need 26 spline side gears from a rear diff to make the axles fit.

BBM keep large numbers of Cro Moly CV's in stock

These are 26 spline units (same as a rear ) so you'll need 26 spline couplers in the diff centre to make them fit.

These are 26 spline units (same as a rear ) so you'll need 26 spline side gears in the diff centre to make them fit.

Bolt on fitting makes removal easy.
Tough, flexible construction (you can bend them over so far the ends touch!)

Can be painted (Use plastic primer first )
Supplied in BLACK

Price is for 2 Flares and a fitting kit.