P0700 on a GMC: Causes, Fixes & Repair Cost

🟠 Moderate severity · drivable

You can usually drive a GMC short-term with P0700, but stop if the transmission slips or will not shift, since that can cause more damage.

What P0700 means on a GMC

On a GMC, P0700 is the transmission control module flagging a stored fault. The specific problem is saved as a separate code in the TCM that a basic OBD2 reader cannot show. GMC trucks and SUVs use electronic automatic transmissions, so P0700 points to the transmission system rather than the engine.

Is P0700 common on GMCs?

P0700 is common on GMC trucks and SUVs with automatic transmissions, especially Sierras, Yukons, and Terrains with higher mileage. Worn clutch packs, failing solenoids, and low fluid are typical triggers. The 6L80 in newer trucks is known for torque converter and valve body faults.

Commonly reported on: Sierra, Yukon, Terrain, Acadia.

Symptoms

Check engine light on
Transmission slipping or delayed shifts
Transmission warning light or limp mode
Torque converter shudder

Common causes

most common: Worn clutch packs or transmission slipping
common: Faulty shift solenoid
common: Low or dirty transmission fluid
less common: Torque converter clutch fault

How to fix it

Fix	DIY?	Typical cost
Read the stored transmission code with a professional scan tool	Mechanic	$80–150
Replace the transmission fluid and filter	Yes	$100–250
Replace the faulty solenoid	Mechanic	$200–600
Rebuild or replace the transmission if it slips	Mechanic	$1800–3500