GT6 Overdrive diff.

[Pete Lewis]

on the 2000 + j type  just the pinion but cant for the life of me remember but im sure there  was no change to the pinion housing

the pinion was same diameter just swapped a 17 for a 18 toothed pinion as now had 14" wheels 

 

on trucks before electronics we had an eccentric hsg, you could turn to match the mesh of different pinions ...easy 

 

 

[johny]

I just cant see how it can be done by changing just one of the two gears. Surely a different number of teeth on one gear changes its diameter and as the spacing of the gears is kept the same then the other gear has to change diameter to keep the teeth engagement the same - or am I missing something?

[johny]

Think Ive got it as theyre not gears but worm and wheel so within reason you can increase or decrease the number of teeth on a wheel of the same diameter without affecting their engagement with the worm too much👍

[Colin Lindsay]

1 hour ago, johny said:

Think Ive got it as theyre not gears but worm and wheel so within reason you can increase or decrease the number of teeth on a wheel of the same diameter without affecting their engagement with the worm too much👍

I did wonder about that myself, how more teeth would mesh correctly (think starter Bendix, 9 or 10 tooth) but all seems to be working fine.

[johny]

Thanks Colin, yes I suppose we're not really talking precision engineering here and full tooth mesh isnt too important😁

[thescrapman]

On 14/11/2023 at 15:32, dougbgt6 said:

I have to say I don't like the look of the 3.27:1 TR7 automatic.

db

I do, it has the best source of a 3.27 available, better carrier and less stressed. Just throw rest of car away after Removing CW&P.

[johny]

Must be a bit of a rare beast though, an auto TR7? Maybe more in the US...

[brian GT6.]

On 12/11/2023 at 19:35, Wagger said:

You need to post 'For sale' in the Courier really.

However, do you know the ratio? Rotate the prop flange 3.5 turns and check if the other two rotate almost once. That would be 3.63:1

If another half turn make them go just past one turn, then it is 3.89:1.

I am looking for a 3.27:1 which would be approx 3.25 turns of the prop for one turn of the other two.

The term 'Overdrive diff' usually refers to differentials that include a built in overdrive. Some Transits had these.

I should have said, " I have an overdrive GT6 for which I have a spare diff."

I will list on ebay.

 

[johny]

Really recommend you carefully count the turns ratio to be sure because over the years lots of bits have been swopped around so now even serial numbers cant be relied apon....