The Mittler Bros. GM 14-Bolt Inner Lineup Pucks are precision-machined round tube alignment rings used in rear-end narrowing applications. With a 3.543″ OD, these inner pucks slip over the 1-1/2″ jig shaft and seat inside the GM 14-bolt bearing bore to ensure accurate, square, and true reinstallation of the housing ends after narrowing.
The GM 14-bolt is a popular heavy-duty rear end found in full-size GM trucks and SUVs — commonly swapped into performance and off-road builds. These pucks allow the full Mittler Bros. rear-end narrowing system to be used on 14-bolt housings. Sold as a pair. Made in the USA.
