SEAT Workshop Service and Repair Manuals

Differential: dismounting and assembling

t	The differential must be adjusted whenever the tapered roller bearings are replaced.

t	The tapered roller bearings must always be removed together. Consult the Adjustments Chart → Chapter.

t	The tapered roller bearings and their corresponding external tracks are matched. Do not mix them up or exchange them with other bearings.

1 -	Gearbox casing

2 -	Adjusting washer S1 for the differential

q	Always of 1 mm thickness

3 -	Outer track, tapered roller bearing

q	Dismounting → Fig.

q	Assembling → Fig.

4 -	Tapered roller bearings

q	Dismounting → Fig.

q	Assembling → Fig.

5 -	Riveted differential crown wheel

q	Dismounting and assembly → Chapter

q	Assembly: consult the Identification Initials section, group assignment, reduction ratios, filling capacities → Chapter

6 -	Friction washer assembly

q	Impregnate with gear oil before assembling

7 -

Sun gear

q	Assembly → Fig.

8 -	Threaded cone for securing the coupled flanges

9 -	Planetary gear

q	Assembly → Fig.

10 -	Planetary gear shaft

q	Take out by tapping with a punch

11 -	Speedometer mechanism pinion

q	Lever out with a flat screwdriver

12 -	Tapered roller bearing

q	Dismounting → Fig.

q	Assembling → Fig.

13 -	Outer track, tapered roller bearing

q	Dismounting → Fig.

q	Assembling → Fig.

14 -	Adjusting washer S2 for the differential

q	Calculate the thickness → Chapter

15 -	Clutch casing

16 -

Bracket

q	Secure the planetary gear shaft in the gearbox with the riveted crown wheel

q	This is fixed with the rivets → Item of the crown wheel

17 -	Spring pin

q	Insert to the centre of the shaft

18 -	Differential housing

q	If replacing, consult the Adjustments chart → Chapter

19 -

Rivet

q	Only for production

q	Drilling → Fig.

q	Assembly with screws → Fig.

20 -	Nut, 70 Nm

21 -	Riveted crown wheel

q	Riveted at the factory

q	Assembly with screws → Fig.

Special tools and workshop equipment required

t	Case of extraction tools for gearboxes -U-40100-

t	Case of tools for repairing gearboxes -U-40200-

t	Pincer extractor tool with grippers -T20022-

t	Electrical blower -SAT 1416-

t	Digital thermometer -SAT 4002-

Dismounting the outer track for the tapered roller bearing   Note! The procedure and the tools needed for dismounting the outer tracks for the tapered roller bearings are the same as for the gearbox casing and the clutch casing. –  Extract the outer track for the tapered roller bearing from the clutch casing using tool -U-40100/2-.

Assemble the outer track for the tapered roller bearing   Note! The procedure and the tools needed for dismounting the outer tracks for the tapered roller bearings are the same as for the gearbox casing and the clutch casing. –  Using tool -U-40200/10- and tool -U-40200/13-, attach the outer track of the tapered roller bearing in the gearbox casing.

Dismounting the tapered roller bearings   Note! The procedure and the necessary tools for attaching the outer tracks of the tapered roller bearings are the same for the gearbox casing and the clutch casing. –  Place tool -U-40200/4- on the differential. –  Place the extractor tool -U-40100/1- over the -U-40200/4- trying to ensure that the grippers are inserted in the notches that are located in the differential box. Extract the bearing. t  If the bearing holder is broken during the extraction process, use tool -T20022- for extracting the inner ring for the bearing.

Assembling the tapered roller bearing   Note! t  Before assembling the bearing in the differential box, heat it to approximately 100°C with the electrical blower -SAT 1416-. The temperature may be checked using the digital thermometer -SAT 4002-. t  The procedure and the tools needed for assembling the tapered roller bearings are the same on both sides of the differential box. –  Assemble the pinion for working the speedometer. –  Place tool -U-40200/19- side B on the bearing and attach it.

Assembling sun gears and planetary gears –  Impregnate the friction washers with gear oil and assemble in the differential housing. –  Fit the differential side gears -A- and attach them with the coupled flanges -B-. –  Introduce a planetary gear and turn it 180°. –  Place a second planetary gear opposite the first. –  In this position, turn the planetary gears towards the inside of the differential housing by means of the coupled flanges until they coincide with the hole on the planetary gear shaft. –  Insert the planetary gear shaft until it goes through the first planetary gear. –  Assemble the threaded cones to secure the coupled flanges and completely insert the planetary gear shaft right to the end. –  Attach the spring pin to secure the planetary gear shaft.

Drilling the rivet heads   Note! t  Protect the tapered roller bearings and speedometer mechanism pinion to prevent possible damage or metal turnings from entering. t  Before and after drilling the rivets, thoroughly clean the differential housing. –  Drill the rivet heads on the opposite side to the speedometer mechanism pinion with a Ø 12 mm bit. –  Drive the rivets out of their housing with the help of a punch.

Securing the crown wheel to the differential housing The rivets removed previously are replaced with screws, nuts and washers → Replacement Parts Microfiche.