Transmission Bench Test
10-13-2011, 01:44 AM
#1
Transmission Bench Test
I recently acquired a used 5-Speed Manual transmission, G28/05. I would like to assess basic functionality on my work bench.
Should I be able to move the input shift rod by hand (have not been able to) or do I need at least a tool like 'special tool 9155' in the factory service manual to have the mechanical advantage needed to select each gear?
Should I be able to move the input shift rod by hand (have not been able to) or do I need at least a tool like 'special tool 9155' in the factory service manual to have the mechanical advantage needed to select each gear?
10-13-2011, 03:04 AM
#2
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I can shift by hand but I have big hands 
also do not stand it up on the rear diff housing( shift rod vertical) and shift gears ! Because if you do it can lock into two gears so when you let out the clutch the car stalls...... You should remove the cover plate and carefully look at the gears/dog teeth but odds are high it needs work unless from a very low miles car.
also do not stand it up on the rear diff housing( shift rod vertical) and shift gears ! Because if you do it can lock into two gears so when you let out the clutch the car stalls...... You should remove the cover plate and carefully look at the gears/dog teeth but odds are high it needs work unless from a very low miles car.
10-13-2011, 03:46 AM
#3
Nordschleife Master
With an 05 almost zero chance it doesn't need something.
10-13-2011, 09:10 PM
#4
I appreciate the responses!
It was sold to me as being removed from a 45k mile car. I figured if the mileage were accurate there was a fair chance it would be in good shape. I'll take off the lid and take a look.
It was sold to me as being removed from a 45k mile car. I figured if the mileage were accurate there was a fair chance it would be in good shape. I'll take off the lid and take a look.
10-14-2011, 04:19 AM
#5
Three Wheelin'
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Look at the dog teeth. These often show wear. If they are worn then you can count on the rest to be worn.
More specifically look for chipped teeth. Minor chipping on the reverse gear is normal, but any chips on the main gears will cause some noise. The gears should turn easily. With the cover off you can use a screwdriver to shift gears. Turning the input shaft a little helps the gears slide. There is a ball bearing detent for each gear. The brass forks should not be worn.
If the trans does not turn easily then the roller bearings are rusted and that means mostly the box is junk. The roller bearing run on a race one one side that can be replaced, but they run on the gears on the other side. Rust removes the plating leaving a rough surface. The other common bearing failure is the front bearing. On the 05 box that bearing is $500 or so if you can get one. Very quickly the cost of parts will make rebuilding the transmission out of the question. The best is to have some cores to get parts from. With VWs my ratio was about 3 to one. I do not know of any generic parts source but I suspect bearings could be sourced and I heard the dog teeth can be got from secondary sources. Soon we will be able to use metal spraying and three D printing to make replacement parts.
Taking one apart and getting it back together requires some prior experience. The 05 box is a pretty easy box to work on but unless you know things to look for it can take a few passes to get it right.
I hope this helps and the box turns out to be a good one. If not I am always interested in transmission and clutch cores.
More specifically look for chipped teeth. Minor chipping on the reverse gear is normal, but any chips on the main gears will cause some noise. The gears should turn easily. With the cover off you can use a screwdriver to shift gears. Turning the input shaft a little helps the gears slide. There is a ball bearing detent for each gear. The brass forks should not be worn.
If the trans does not turn easily then the roller bearings are rusted and that means mostly the box is junk. The roller bearing run on a race one one side that can be replaced, but they run on the gears on the other side. Rust removes the plating leaving a rough surface. The other common bearing failure is the front bearing. On the 05 box that bearing is $500 or so if you can get one. Very quickly the cost of parts will make rebuilding the transmission out of the question. The best is to have some cores to get parts from. With VWs my ratio was about 3 to one. I do not know of any generic parts source but I suspect bearings could be sourced and I heard the dog teeth can be got from secondary sources. Soon we will be able to use metal spraying and three D printing to make replacement parts.
Taking one apart and getting it back together requires some prior experience. The 05 box is a pretty easy box to work on but unless you know things to look for it can take a few passes to get it right.
I hope this helps and the box turns out to be a good one. If not I am always interested in transmission and clutch cores.
