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Randy's Transmissions  |  SKU: 22121B-01K

Sonnax 47/48RE Input Shaft & Piston Kit

Regular price USD 1,10300

Can I pick up my order or have it installed at your shop?

Absolutely. We offer local pickup on most products and full professional installation at our shop in Washington, MO. Whether you just want to grab your parts or have our techs handle the install, we’ve got you covered. Give us a quick call at 636-429-7020 or message us to schedule a visit — we’ll make sure the parts are ready when you arrive.

How do I know if this part fits my vehicle?

Unsure if it’ll fit? No problem — that’s what we’re here for. Send us your vehicle’s year, make, and model, and we’ll verify fitment before you order. We can also point you toward compatible upgrades or supporting parts if needed.

What if I need to return a product or it’s defective?

Most unused items can be returned within 30 days in their original packaging. Some products are covered by a manufacturer’s warranty as well. If something arrives damaged or doesn’t meet your expectations, just let us know — we’ll help you get it replaced, refunded, or repaired. (Tracking updates are also emailed automatically once your order ships.)

What's the lead time on custom or fabricated parts?

Many of our parts are built to order — especially fabricated or performance components. These can take additional time to produce before shipping. Lead times vary by manufacturer and demand, but we’ll always keep you updated along the way. If you’re working on a tight schedule, reach out before ordering at 636-429-7020 and we’ll confirm current availability or estimated ship dates.

Description

<p>Based on the ultra-durable, one-piece Sonnax heavy duty input shaft 22121B-01 for Chrysler 47RE, 47RH, and 48RE units, the Smart-Tech input shaft and piston kit 22121B-02K has a hub with longer direct (front) clutch splines. Combining longer splines with a thinner billet aluminum direct piston allows for one extra (OE-thickness) direct friction plate, while keeping OE-thickness steels, backing plate, OE waved retaining ring and OE clutch clearances.</p>
<p>Some common aftermarket modifications designed to include extra clutches require reduced steel thickness and decrease the heat absorption capacity of the clutch pack, others reduce clearance and eliminate the waved retaining ring, which contributes to excessive 2-3 shift overlap. The Sonnax kit <span class="bx-pager">avoids these problems </span>by increasing the number of frictions from five to six, adding to the steel mass of the clutch pack, and maintaining the OE thickness backing plate and clearances for the optimum combination of increased capacity and durability.</p>