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The input shaft seal is one of the cheapest parts in your transmission and one of the most expensive to replace, because of where it lives. On an automatic, the input shaft is the torque converter hub sealing surface at the very front of the transmission, riding inside the front pump. The seal there keeps fluid from weeping out the front of the case where the converter enters. To get to it, the transmission has to come out of the vehicle and the converter has to come off. That is the whole cost story: a $10 seal behind $600 to $1,200 of labor.
Expect a total of $650 to $1,400 at an independent shop for most rear-wheel-drive vehicles, and $900 to $1,800 at a dealer or on a transverse front-wheel-drive layout where the transmission is harder to drop.
Input Shaft Seal vs Front Pump Seal — Clearing Up the Confusion
People use these names interchangeably and they are not always the same thing. On most automatics there is one seal at the front of the pump that the torque converter hub rides in. Depending on the transmission family, that seal is called the front pump seal, the converter seal, or the input shaft seal. On some designs there is also a separate lip seal or bushing on the input shaft itself behind the pump.
What matters for cost: if the leak is at the very front where the converter meets the case, the labor is the same regardless of which seal it turns out to be, because the transmission comes out either way. If you are chasing an external front leak, start with our front seal leak diagnosis and our front pump replacement cost page.
Parts vs Labor Breakdown (2026)
| Line Item | DIY Cost | Shop Cost |
|---|---|---|
| Input shaft / front pump seal | $8 - $25 | $15 - $40 (marked up) |
| Torque converter hub seal / bushing | $10 - $30 | $20 - $50 |
| Transmission fluid (refill) | $40 - $120 | $70 - $180 |
| Pan gasket / filter (done while in there) | $20 - $60 | $40 - $110 |
| Labor (R&R transmission, 5-9 hrs) | $0 | $600 - $1,300 |
| Typical total | $80 - $230 | $650 - $1,800 |
The seal itself is almost free. What you are paying for is roughly 5 to 9 hours of book time to remove and reinstall the transmission, plus fluid. That is why shops often recommend doing the front pump seal, converter seal, and pan service all at once, since the transmission is already out. It is the same reason it is worth pricing a reman or rebuild if the unit has other issues, since you are already paying the removal labor.
What Drives the Price Up or Down
- Layout. A body-on-frame RWD truck is the cheapest to drop the trans from. A transverse FWD car, especially with the subframe and axles in the way, adds hours.
- All-wheel drive. AWD adds transfer case and driveshaft removal, another 1-2 hours.
- Converter bushing wear. If the converter hub has scored the bushing that supports the seal, the shop has to replace the bushing too, or the new seal fails in months. Do not skip this.
- Dealer vs independent. Dealer labor runs $160-$220/hr in 2026 vs $110-$150 at a good independent. Same seal, very different bill.
- Sealing surface damage. A groove worn into the converter hub means a new or reman converter, adding $150-$500.
Is It Worth Fixing, or Just Live With the Leak?
A slow front seal seep that drops a few spots on the driveway can sometimes be monitored. But a converter-hub seal that is actively leaking under pressure will lower your fluid level, and low fluid on an automatic causes slipping, overheating, and clutch damage that costs far more than the seal job. If you are topping off more than a quart every few thousand miles, fix it. If it is a stain that never moves, watch it and keep the fluid full.
Because the labor is fixed no matter what, the smart move when you are already paying to pull the transmission is to refresh the pan filter, gasket, and both front seals in one visit so you are not paying that removal labor twice.
Seals and Kits Ship Same-Day
Doing the job yourself or supplying your own parts to save the markup? gearboxinsider.com stocks front pump seals, converter hub seals, bushings, pan kits, and fluid by transmission model. Same-day ship before 2pm Eastern, free shipping.
Shop Gearbox Insider →FAQ
Can I replace the input shaft seal without dropping the transmission?
No. The seal sits inside the front of the transmission behind the torque converter. The converter has to be removed to access it, and the converter cannot come off with the transmission in the vehicle. The trans comes out.
How long does a front pump / input shaft seal last after replacement?
A properly installed seal with a good sealing surface lasts the life of the transmission. Premature failure almost always means the converter hub was scored or the bushing was worn and not replaced.
Why is such a cheap part so expensive to replace?
You are not paying for the seal. You are paying for 5 to 9 hours of labor to remove and reinstall the entire transmission just to reach it.