Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnostic Aids
1995 GMC Suburban K2500, 7.4 NSECTION Diagnostic Aids
DTC 85 will set when an unknown gear ratio is detected for any gear but 4th. Note commanded gear and incorrect ratio. Check transmission fluid level. Compare scan tester gear ratio reading to specifications in GEAR RATIO table.
GEAR RATIO
| Gear | Less Than | More Than |
|---|---|---|
| 1st | 2.38 | 2.63 |
| 2nd | 1.43 | 1.58 |
| 3rd | .95 | 1.05 |
| Reverse | 1.97 | 2.17 |
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.