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.
General Repair Notes
To ensure flawless and successful transmission repairs, the greatest care and cleanliness as well as the use of good and proper tools is essential. The usual basic safety precautions also, naturally apply when carrying out vehicle repairs.
A number of generally applicable instructions for individual repair operations, which are otherwise mentioned at various points in the article, are summarized here. They apply to this article.
Transmission
- Observe rules of cleanliness for working on the transmission → Rules for cleanliness when working on transmission .
- After transmission repairs, clean ATF lines and ATF cooler → 37 - AUTOMATIC TRANSMISSION - CONTROLS, HOUSING .
- Reusable components must be cleaned, checked and reconditioned if necessary before installation → Transmission components, evaluating wear
- The old transmission should be installed and put into operation as quickly as possible to prevent corrosion on the newly installed components.
After installing, following fluid levels must be checked and topped off if necessary:
- Top off ATF level after repair → 37 - AUTOMATIC TRANSMISSION - CONTROLS, HOUSING .
- Gear oil in front final drive → 39 - FINAL DRIVE, DIFFERENTIAL .
- Capacities and specifications → 00 - GENERAL, TECHNICAL DATA .
O-rings, gaskets, seals
- O-rings, gaskets and seals must be replaced.
- After removing gaskets, examine contact surface on housing/shaft for burr resulting from removal or for other signs of damage.
- Open sides of oil seals face fluid side.
- To install, thinly coat gaskets along outer circumference and on sealing lip with ATF.
- Coat O-rings with transmission fluid or Vaseline before inserting to prevent crushing rings during installation.
- Use only ATF or Vaseline in areas near ATF. Other types of lubrication cause malfunctions to occur in the transmission hydraulics.
- When pressing in new gaskets, make sure the sealing lip does not run on the same point as the sealing lip of the old seal (use insertion depth tolerances).
- Replace paper seals, always clean sealing surfaces and remove old seals completely.
Bolts and nuts
- Loosen bolts in reverse order of tightening.
- Loosen and tighten bolts and nuts for securing covers and housings in a diagonal sequence and in stages, when no tightening sequence is specified.
- The tightening torques stated apply to unoiled bolts and nuts.
- Replace self-locking bolts and nuts.
Locking elements
- Do not over-stretch circlips.
- Always replace circlips which have been damaged or over-tensioned.
- Circlips must be properly seated in the base of the groove.
- Replace spring pins. Installation position: Slot is longitudinal to line of force.
Bearings
- Slightly grease mount with ATF before inserting.
- Attach mount and adjustment shims only with Vaseline. Other lubricants cause malfunctions of the hydraulic transmission controls.
NO RELATED
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.