lt77 gear ratios

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shortysshaker
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lt77 gear ratios

Post by shortysshaker »

does anyone no the gear ratios on 1st 2nd 3rd 4th & 5th on a lt77 box witch I beleave is a Sherpa box id number 17A0009247D


sidecar
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Post by sidecar »

Dunno about your suffix but I don't think they differed too much anyway...

http://www.keirhague.com/gearboxes.html
DaveEFI
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Re: lt77 gear ratios

Post by DaveEFI »

shortysshaker wrote:does anyone no the gear ratios on 1st 2nd 3rd 4th & 5th on a lt77 box witch I beleave is a Sherpa box id number 17A0009247D
I can give you the ratios for an SD1 box from the BL manual. Van boxes have wider spaced ratios, IIRC. If you have the box out of the vehicle, it's easy to work out the ratios.
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softdash3.9
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Post by softdash3.9 »

G17A SD1 2300/2600 5 speed
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shortysshaker
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Re: lt77 gear ratios

Post by shortysshaker »

DaveEFI wrote:
shortysshaker wrote:does anyone no the gear ratios on 1st 2nd 3rd 4th & 5th on a lt77 box witch I beleave is a Sherpa box id number 17A0009247D
I can give you the ratios for an SD1 box from the BL manual. Van boxes have wider spaced ratios, IIRC. If you have the box out of the vehicle, it's easy to work out the ratios.
yes the box is out,how s the best way to work outthe ratios? thanks lee
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Post by DaveEFI »

Mark the input and output shafts with Tippex or whatever. Count the number of turns for each one in each gear.
4th is direct, so both shafts will have the same number of turns.

Ist - if an SD1 box - will have 3.321 turns of the input shaft to one of the output shaft. A Sherpa box has 4. something - so easy to tell.
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ChrisJC
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Post by ChrisJC »

I mark the input and output shafts, and then turn / count both ends until both ends have made an exact whole number of turns.

So you might get 33 turns of the input to 10 turns of the output which would be a ratio of 3.3

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Post by sidecar »

ChrisJC wrote:I mark the input and output shafts, and then turn / count both ends until both ends have made an exact whole number of turns.

So you might get 33 turns of the input to 10 turns of the output which would be a ratio of 3.3

Chris.
That's what I did with and old R380, it is much better than just doing one turn of the input shaft. It can 'do your head in' counting turns on two shaft, having a second person helps!
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Post by DaveEFI »

Do two columns (input and output) on a sheet of paper and put a tick on them each time the shafts pass zero.
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