Shop Rebuild Kits →
The first thing to understand is that "rebuild kit" means three completely different things depending on the tier, and the price gap between them is the whole game. A bare overhaul kit and a full master kit for the same transmission can be $90 apart, and the difference is whether you get the hard parts that actually wear. Buy the wrong tier and you either overpay for steels you did not need or pull the trans twice because you skipped the bushings.
Here is the tier ladder, cheapest to most complete:
- Banner / overhaul kit: gaskets, seals, sealing rings, O-rings, the metal-clad seals. No friction plates, no steels, no hard parts. For a leak job or a unit that only needs sealing.
- Master kit: everything in the banner kit plus the friction clutch plates, steel plates, and usually the band(s). This is the standard rebuild kit for a worn-out transmission.
- Master kit with hard parts / "deluxe": master kit plus bushings, thrust washers, filter, and sometimes a pump or sprag. The complete job in one box.
- Heavy-duty / performance kit: upgraded high-energy frictions, Kolene or upgraded steels, and often a shift-improvement component for towing or power builds.
Rebuild Kit Cost by Tier (Common GM/Ford Units, 2026)
| Kit Tier | What's Included | Typical Price |
|---|---|---|
| Banner / Overhaul | Gaskets, seals, rings only | $45 – $110 |
| Master Kit | Banner + frictions + steels + bands | $130 – $260 |
| Master + Hard Parts | Master + bushings, washers, filter | $200 – $380 |
| Heavy-Duty / Performance | HD frictions, upgraded steels, shift kit | $300 – $550 |
The Brands — What You're Paying For
Transtec (Freudenberg-NOK) — The Gasket and Seal Benchmark
Transtec is the name builders trust for the sealing side of a kit. They make OE-quality bonded pistons, metal-clad seals, and Wide Band sealing rings. When a master kit lists "Transtec overhaul kit included," that is a quality signal — you are getting seals that will not weep at 30k miles. A Transtec banner kit alone runs roughly $50-$110 depending on the unit. Many premium master kits are built on a Transtec gasket-and-seal base plus another brand's frictions.
Check Transtec kits
Raybestos — The Friction Plate Standard
Raybestos is the friction material most builders reach for. Their GPZ and Z-Pak high-energy frictions hold up to heat and clamp better than economy plates, which is why they show up in HD and towing kits. If you tow or you are rebuilding a unit that cooked itself, paying up for Raybestos frictions is the difference between a rebuild that lasts and one that glazes over again. Expect a friction-and-steel module to add $80-$180 over a base kit.
Check Raybestos friction kits
Alto — Frictions, Steels, and Red Eagle
Alto is the other major friction and steel maker. Their Red Eagle high-energy frictions and Kolene-treated steels are a popular performance pairing, and Alto often packages complete master kits at a slightly lower price than a Raybestos-based equivalent. Quality is genuinely good; the choice between Alto and Raybestos is more about builder preference than a clear winner.
Check Alto Red Eagle kits
Sonnax — Not a Kit, But the Upgrade You Add
Sonnax does not sell full rebuild kits; they sell the fixes for the design flaws in your specific transmission — oversized valve-body parts, billet drums, reinforced sprags, and boost valves. Budget $30-$150 on top of your kit for the one or two Sonnax parts that address your unit's known weak point. Skipping the Sonnax fix is the most common reason a "rebuilt" transmission fails the same way the original did.
Check Sonnax upgrade parts
How to Pick the Right Tier
- Leak or sealing issue only, frictions still good? Banner kit. Do not pay for plates you do not need.
- Worn-out daily driver, standard rebuild? Master kit with quality frictions. This is 80% of jobs.
- Pulling the trans is a pain and you want one-and-done? Master plus hard parts, so you replace bushings and washers while it is open.
- Tow, plow, or power build? Heavy-duty kit with high-energy frictions and the Sonnax fix for your unit. Do not run economy frictions behind heat.
The cheapest path to a second rebuild is buying a $130 master kit, skipping the $40 hard parts and the $60 Sonnax fix, and reusing worn bushings. Spend the extra $100 the first time.
Get the Right Kit — Ships Same-Day
gearboxinsider.com stocks banner kits, master kits, HD friction modules, and the Sonnax fixes for your exact transmission, with techs who know which tier your build needs. Same-day ship before 2pm Eastern, free shipping on every order.
Shop Gearbox Insider →FAQ
Is a cheap import master kit worth it?
For a low-mileage seal job, sometimes. For an actual worn-out rebuild, no — the frictions and steels are where the savings come from, and that is exactly where you do not want to cut. Pay for known-brand frictions.
Do I need a torque converter too?
Almost always. If the transmission failed, the converter likely has debris in it and worn lockup material. Most kits do not include a converter; budget $120-$350 for a quality reman or new unit on top of the kit.
What is the total parts cost to rebuild myself?
For a common GM or Ford automatic: a quality master kit ($150-$280), a torque converter ($120-$350), fluid ($60-$120), and any Sonnax fix ($30-$150). Roughly $400-$800 in parts for a solid DIY rebuild, versus $2,000-$4,000 at a shop.