10L90 Rebuild Cost and What Drives It

The 10L90 sits behind the loudest engines GM has built in the last decade: the LT4 in the Camaro ZL1, the supercharged V8s in the CT5-V Blackwing and Escalade-V, and the CT6 above them. The owners of those cars get two rebuild quotes that are thousands of dollars apart and assume one shop is padding. Usually the shops priced two different jobs and called both of them a rebuild.

This is the line-by-line of where the money goes on a 10L90, which items move the total, and the checks that sometimes make the repair free. Part numbers and specs come from GM, NHTSA, ATRA, Sonnax and Raybestos, listed at the bottom. Where I give a number from my own bench, I say so.

Recommended 10L90 parts

The three line items every 10L90 rebuild quote should include: valve body repair parts for the worn bores, a new filter and pan gasket, and DEXRON ULV for the refill. Ships from the USA, secure checkout.

Sonnax 10R80/10R90 Zip Kit Ford GM 10-Speed Valve Body

$259.99View part

10L60/10L80/10L90 Transmission Filter and Pan Gasket Kit

$30.99View part

ACDelco Dexron ULV ATF for GM 10-Speed Automatics, 1 Quart

$17.99View part

Step one: find out who is paying

Run the VIN before you price anything. On this transmission the answer changes the whole conversation.

• Cadillac cars and the Escalade-V. GM's warranty pages list Cadillac's powertrain limited warranty at 6 years or 70,000 miles, whichever comes first. GM Fleet's summary adds that it is fully transferable with no fees and no deductible. There is one catch: Cadillac says 2023 Escalade-V coverage is subject to a 6-month retention policy from delivery, and a transfer before that voids the bumper-to-bumper and powertrain coverage. A used Escalade-V that changed hands early may have nothing left.
• Camaro. Chevrolet retail coverage is 5 years or 60,000 miles on the powertrain, also transferable. A 2022 ZL1 bought secondhand can still be inside it.
• Open recall. NHTSA recall 25V-148 (GM N242480630) covers 90,081 vehicles with the 10-speed: the 2020–2022 Camaro, the 2020–2021 CT4 and CT5, and the 2019–2020 CT6. GM's filing blames valve body wear causing a fluid leak and a pressure drop that can momentarily lock the rear wheels on a downshift from 8th. The remedy is TCM software, not a new valve body, but a car that has not had it done belongs at the dealer before it belongs on your lift.

The recall matters for pricing in a second way. The updated software detects valve wear roughly 10,000 miles before a lock-up could happen and then limits the transmission to 5th gear with a reduced propulsion message. A customer who walks in "stuck in fifth" often has a 10L90 that is mechanically fine except for one worn bore. That is a valve body job, not a rebuild, and quoting a full overhaul on it is how you lose the customer.

The three jobs that all get called a rebuild

Line item 1: the valve body, repaired or replaced

This is the single biggest swing in any 10L90 quote. On this unit the solenoids are direct-acting and push straight on the clutch regulating valves, so the wear lands in the valves and bores, not the coils. There are two ways to deal with it, and they are priced very differently.

Repair the body you have

Sonnax lists a full valve kit program for the 10L90. On the Gen. 1 body (built before late 2019) that includes the main pressure regulator kit 105740-12K (oversized 105740-20K), TCC priority 105740-03K, oversized TCC regulator 105740-16K, LPC signal damper 105740-04K, solenoid stabilization retainer 105740-19K and clip insert 105740-01K, plus latch valve kits 105740-47K or oversized 105740-71K. Sonnax says every 10-speed rebuild should replace or modify the latch valves, so budget them on every Gen. 1 job, not only the ones that test bad.

Gen. 2 bodies drop the latch valves and use feed limit low and feed limit high valves instead. Sonnax's drop-in kits are 105740-54K and 105740-58K, with oversized versions when a bore reads below 8 in-Hg on the vacuum gauge. The kits themselves are small money, mostly $10 to $90 each at our sister store's current list prices. The real costs are the bench hours to vacuum test every bore and the tooling: the reamer kits and Sonnax's clutch control valve bore sizing tool 105740-BST. A shop that owns those can quote the repair path. A shop that does not will quote you a new body.

Replace the body

ATRA's GEARS magazine is blunt about when repair is off the table: wear in the LPC accumulator bore or the linear pintle solenoid bores means a new valve body. The linear pintle solenoids were not sold separately when GEARS published, so you order a complete body and program its Part Unique Number (PUN) or Mechanical Characterization and Virtual Matching (MCVM) data into the TCM. GM's preliminary information PIP5654A exists because techs kept failing that step; a letter O in the PUN gets read and typed as a zero, and the software rejects it. Add scan tool access and programming time to any quote that includes a new body.

On the trucks there is now a Gen. 3 service body (24071206 diesel, 24071207 gas) with a redesigned default circuit. Sonnax says both fit only ETRS trucks with electronic park control. Do not price one for a Camaro or a CT5 without confirming fitment by VIN.

Line item 2: clutches

The 10L90 is a clutch-to-clutch unit with six clutches, A through F. Raybestos's GPZ friction module for it, RGPZ-269, lays out the count: 3 A, 5 B, 6 C, 7 D, 5 E and 4 F frictions. That is 30 friction plates, and the matching steel module, STMGM32, carries its own stack of steels and pressure plates. Per ATRA, the C, D and E clutches carry the most engagements, so those packs are where heat shows first.

This is where 10L90 pricing splits from the 10L80. A stock Camaro SS or CT6 that failed from a leaking bore can usually go back together with an OE-style friction set. A ZL1, Blackwing or Escalade-V with a pulley, tune or drag radials is a different job. Raybestos markets its GPZ set because stock clutch failure is common on cars chasing 9-second passes, and the performance frictions cost more than twice what an OE-style set does. At our sister store's current list prices, the BorgWarner 10L90 friction kit is $179.99 and the Raybestos 10L90 friction kit is $413.99. Steels run $603.99 to $651.99 as a full module. Most builds reuse steels that measure flat and show no heat, which is why the steel line swings so much between quotes.

Clearance is not optional on this unit. GEARS warns that if clutches are outside the specified clearance range, the TCM strategy cannot compensate, and the result is harsh or binding shifts. Excessive clearance is on its list of common high-mileage findings. A quote that includes new frictions but no time to measure and set clearance is a quote for a comeback.

Line item 3: sealing rings, seals, bushings, filter and fluid

Small money, not negotiable. GEARS states that the rotating sealing rings must be replaced on a 10L rebuild, because reused rings leak and cause intermittent shift quality problems. Beyond that:

• Gasket and seal kit ($239.99 at our sister store) and bonded pistons if any are lifting ($156.99 for the set).
• Case bushing kit if the bushings show wear ($111.99 to $220.99 depending on the kit).
• Filter and pan gasket. GM part 24294355 covers the 10L60, 10L80 and 10L90; ours is $30.99.
• Fluid. GM's 2025 capacities chart lists the 10L90 as RPO MHX in the CT5 and RPO MHO in the Escalade and ESV, both at 7.7 liters (8.1 quarts) of DEXRON ULV for a fluid change. A dry rebuilt unit and a dry converter take more than that. ULV is a different specification from the DEXRON HP used in the 8-speeds; the wrong bottle will make a fresh build shift like a worn one.

If you want the soft parts in one box, the 10L90 rebuild kit at our sister store is $954.99 for 2017-up units. It is a useful baseline for comparing quotes: if a shop's soft-parts rebuild costs less than a kit plus frictions and fluid, ask what was left out.

Line item 4: the torque converter

This is the swing item nobody likes to talk about at quote time. If the complaint included shudder or TCC slip, or the pan had friction material in it, the converter goes. Debris from burned clutches lives in the converter, and reusing it contaminates the new build. On the high-output cars, a converter rated for the power adds more. A quote that does not say either way about the converter is incomplete.

Line item 5: labor, relearn and the checks that cancel the job

Labor is the half of the bill the parts list never shows. A valve body job keeps the case in the car. A full rebuild is removal, teardown, inspection, valve body work, clearances, reassembly, installation, refill and Fast Learn, and shop rate does the rest of the math. My bench opinion: in cars like the CT5-V and Camaro, where exhaust and driveshaft work add time to the R&R, labor is often bigger than the soft parts.

Before the pan comes down, three cheap checks sometimes end the conversation:

1. Cooler line. GM's PIP5792E covers 10L80 and 10L90 vehicles with harsh shifts, shudder, surge, stall or above-normal fluid temperature, and names a twisted cooler line as the root cause on low-mileage units. Untwisting the line can fix it.
2. Battery and voltage. Sonnax has traced post-repair harsh engagements and erratic shifts on 10-speeds to weak batteries. Test the battery before you condemn hydraulics.
3. Fluid type and level. Confirm DEXRON ULV at the correct hot level before any teardown.

FAQ

How much does a 10L90 rebuild cost?

It depends on which job is actually needed. A valve body repair with Sonnax kits is a few hundred dollars in parts plus bench time, a full soft-parts rebuild adds a clutch set, sealing rings, gaskets and about a gallon or more of DEXRON ULV, and a replacement valve body or reman unit is the top of the range. Labor and whether the converter goes decide the rest. Check warranty and recall 25V-148 first, because either can take the cost to zero.

Is a 10L90 rebuild covered under the Cadillac powertrain warranty?

Cadillac's powertrain limited warranty runs 6 years or 70,000 miles, whichever comes first, and it transfers to the next owner with no fees or deductible. The 2023 Escalade-V has a 6-month retention rule, and a transfer before that voids the new vehicle coverages. Chevrolet's Camaro coverage is 5 years or 60,000 miles for retail buyers.

How much fluid does a 10L90 take?

GM's 2025 capacities chart lists the 10L90 (RPO MHX in the CT5 and MHO in the Escalade) at 7.7 liters, 8.1 quarts, of DEXRON ULV for a fluid change. A rebuilt unit that starts dry, plus a dry converter, takes more than that, so plan on extra ULV and set the level hot per the service procedure.

Can you rebuild a 10L90 valve body or do you have to replace it?

Most wear can be repaired with Sonnax drop-in or oversized valve kits after a vacuum test. ATRA's GEARS magazine says wear in the LPC accumulator bore or the linear pintle solenoid bores means a new valve body, and because the solenoids were not sold separately, the new body's PUN or MCVM data has to be programmed into the TCM.

Are the 10L90 clutches the weak point in a rebuild?

On a stock street car the valve body usually fails first. On a modified ZL1, CT5-V Blackwing or Escalade-V, clutch failure is common, and Raybestos markets its GPZ friction set for exactly that. The 10L90 has six clutches, A through F, with 30 frictions in the Raybestos module, so the clutch set is a real line item on any teardown.