Why does my 2004–2008 Acura TL flare or slip between gears?

Short answer: The 2004–2008 TL's automatic is known for a flare (revs jump between gears) or slipping, usually on the 2–3 or 3–4 shift. Owners often start with new transmission pressure switches and a series of fluid changes with Honda fluid. If it keeps slipping, the clutches inside are wearing and it needs a rebuild.

Symptom: The engine revs up briefly between gears, a slip on the 2–3 or 3–4 shift, harsh shifts, or a blinking D light.

What to check first

1. Check the fluid level and condition and use only Honda ATF.
2. Ask about the 3rd and 4th gear pressure switches. AcuraZine's diagnostic guide points owners to these first.
3. Do the fluid changes in a series. Owners often drain and fill several times to refresh most of the fluid.
4. Note whether the slip is getting worse. A worsening slip means clutch wear.

Likely causes

1. Worn 3rd/4th gear pressure switches. A common, cheap first fix per AcuraZine.
2. Old or wrong fluid. Fresh Honda fluid often improves shifts.
3. Worn 3rd clutch pack or internal wear. Slipping that gets worse points to internal wear and a rebuild.

What it usually costs

Pressure switches and fluid are inexpensive. I couldn't find a reliable current price for a TL transmission rebuild, so get written quotes from a transmission shop and compare used or remanufactured options.

Is it safe to keep driving?

A mild flare can be driven short term while you get it checked. Real slipping, a blinking D light, or loss of drive means stop and get it looked at; a transmission that lets go in traffic is dangerous.

DIY or shop?

Pressure switches and drain-and-fill are DIY for many owners. Internal repairs are shop jobs.

Recalls, bulletins and complaints in plain words

• Recall 04V176 (includes 2004 TL): heat could build up at the second gears in the automatic, causing chipped or broken gears. Dealers revised the cooler return line or replaced the transmission if gears were damaged. Check your VIN.
• Acura TSB 08-018 covers a 3rd-gear grinding issue on the manual TL, not the automatic.
• NHTSA complaints: 135 of 1,434 TL complaints from 2004–2008 mention the transmission, slipping, shifting or flare.

What owners report

• AcuraZine's 3rd-gen TL thread asking if they have transmission problems like the 2nd gen collects owner reports of flare and slip.
• An AcuraZine owner asked if their transmission was on its last leg and posted pictures of what they found.
• Another AcuraZine "3rd gear issue" thread focuses on problems around third gear.

My take

My advice as a former pre-purchase inspector: on a used TL, drive it with a light foot through every gear, especially the 2–3 shift. A revs-jump between gears is something you want priced in before you sign.

Vehicle focus: 2004–2008 Acura TL with the 5-speed automatic (manual cars have a separate 3rd-gear bulletin).

Safety / mechanic note

A slipping transmission can lose drive suddenly. Get it checked before long trips. Verify with a mechanic.