Wranglers are a high-frequency platform in most markets — there are a lot of them, they get used hard, and the owners are often the type to defer maintenance until something actually breaks. Here's what I keep on hand to handle the three transmission types without waiting on parts. — Input shaft bearing (Timken or SKF): The most common mechanical failure. One on the shelf. — 3rd/4th synchronizer hub: Second most common. One unit in stock. — Full synchro ring set (all gears): If you're opening an NSG370, replace all synchro rings. They're cheap insurance — a full set runs $60–$90 — and coming back in for a synchro you didn't replace is a warranty call you don't want. — GL-4 75W-85 gear oil, 4 quarts minimum: Do not stock GL-5 for this unit.
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Timken Input Shaft Bearing Kit — NSG370 Compatible
OEM-quality bearing for the NSG370 input shaft — Timken is the correct spec for this application and the one I stock for JK Wrangler manual transmission work.
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