Chevy & GM
Transmission Repair.
Silverado, Tahoe, Sierra, Camaro, Corvette or a classic with a TH350 — we repair and rebuild GM automatics from the 700R4 and 4L60E to the 6L80 and 8L90.
Number One Transmissions repairs and rebuilds Chevrolet and GM transmissions from our Oakland Park shop, serving Fort Lauderdale and all of South Florida since 1983. We work on the 4L60E, 4L65E, 4L70E, 4L80E, 6L80, 6L90, 8L90, TH350, TH400, 700R4 and 200-4R, and we sell rebuilt GM units built and dyno-checked in our own shop. Free diagnosis, honest estimate, 1-year / 12,000-mile warranty. Call (954) 535-9393.
Expert Chevy & GM transmission repair in South Florida
GM automatics are some of the most common transmissions on the road — and some of the ones we know best. From Silverados and Tahoes to Camaros, Corvettes, G-bodies and classic C10s, three generations of our family have torn down, rebuilt and upgraded GM transmissions. When one comes in, we usually know where to look first.
The 4L60E and 4L65E, found in countless half-ton trucks, SUVs and Camaros, are known for failures like a worn 3-4 clutch pack, a broken reaction sun shell, and 2-4 band wear — often showing up as a lost gear or no reverse. The 4L70E is a stronger evolution, and the heavy-duty 4L80E lives behind big engines and three-quarter-ton trucks. We rebuild them with the known weak points upgraded, not just replaced with the same parts that failed.
The newer six- and eight-speed units take more diagnosis. The 6L80 and 6L90 commonly come in with torque-converter shudder, harsh shifts, or control-module and valve-body faults. The 8L90 in late-model trucks, Camaros and Corvettes is known for shudder complaints that can be tied to fluid as well as hardware — so the right fix starts with the right diagnosis, not a guess.
And then there are the classics. The TH350 and TH400 three-speeds, the 700R4 and the 200-4R overdrives are staples of hot rods, muscle cars and swaps, and we build them for everything from cruisers to big-power street cars. We sell rebuilt GM units in our rebuilt transmission catalog and ship them nationwide.
Signs your Chevy or GM transmission needs attention
If your vehicle is showing any of these, bring it in for a free diagnosis before a small problem becomes a big one:
On a 4L60E, losing a gear or flaring between 3rd and 4th often points to a burnt 3-4 clutch pack.
A sudden loss of reverse, or of 1st and reverse, is a classic 4L60E internal failure. Stop driving and get it checked.
A shudder at steady speed on a 6L80 or 8L90 can be the torque converter or fluid-related — it needs proper diagnosis.
A hard clunk into drive or a delay before it engages points to pressure, valve-body or solenoid problems.
Slipping while towing or accelerating hard usually means worn clutches or low line pressure.
Late, soft or no upshifts on a 700R4 or 200-4R often trace back to TV-cable adjustment or internal wear.
How we handle your Chevy & GM transmission repair
The same honest, four-step process on every job — a solution, not a guess:
Free Diagnosis
We road-test, scan codes and live data, check fluid and pressure, and confirm exactly which GM unit you have.
Honest Estimate
You get a written estimate for the fix you actually need — repair, rebuild, or a rebuilt replacement.
Repair or Rebuild
From a valve body or converter to a full rebuild with the known GM failure points upgraded, all in-house.
Test & Warranty
We road-test and verify every shift, then back the work with a 1-year / 12,000-mile warranty.
Why South Florida trusts Number One Transmissions
A transmission is not a job for a general shop. Here’s what you get with a dedicated, family-owned specialist:
- 40+ years, three generations — a true transmission shop, not a franchise.
- ASE-certified, licensed & insured, A+ BBB accredited.
- Free diagnostics & honest estimates — the price we quote is the price you pay.
- 1-year / 12,000-mile warranty on every repair and rebuild.
- 4.6★ across 229 Google reviews — nearly every one names owner Chris.
- Veteran & first-responder discount.
Trusted by South Florida drivers.
Questions, answered.
How much does Chevy transmission repair cost?
Why does my 4L60E keep losing gears?
What causes 8L90 or 6L80 shudder?
Do you rebuild TH350, TH400 and 700R4 transmissions?
Can you ship a rebuilt GM transmission?
Do you work on Silverado and Sierra HD trucks?
Tell us what it’s doing.
Free diagnosis, honest estimate, and a straight answer — from South Florida’s transmission specialists since 1983.