The Toyota Landcruiser Owners Club

[diggerdave]

I would like to replace my front differential, which is labelled R16 on the extension tube.  I believe a 4.1:1 diff was fitted to vehicles like mine (manual diesel SWB with OE small 215/80/16 tyres and no wheelarch flares).

My questions are:

a) is it correct to say that R16 refers to the 4.1 ratio of my diff, so swapping an R16 for another R16 would be ok?

b) there are other codes out there.  I believe R17 refers to the more common 4.3:1 ratio, BUT what do the labels R57, R57 and R27 (all of which are found on Colorado/90 series diffs) mean?

Does anyone have a definitive answer?  R16 diffs are hard to find so need to know if I could swap another one

Cheers,

Dave
_________________
1997 KZJ90 3.0d, 2" suspension lift, 235/85/16 Cooper STT Pros. 217k hard miles

[Google]

[mike adams]

Hi
Like you I have a '97 SWB no flares GS model. I thought they had the lower 4.3:1 gearing. I fitted a 6 speed box to mine but it still seems undergeared. Goes very well but still seems like it needs another cog. What revs does yours show at 70mph?
Regards
Mike Adams

[diggerdave]

Hi.  I definitely have an R16 sticker on the diff tube and what little information there is out there suggests that that is a 4.1 ratio.

At 70 I'm at around 2800 revs but it doesn't mean much unless you've got the same size tyres.  I'm on 265/75/16 (Original Equipment was 215/80/16 if I remebre right)
_________________
1997 KZJ90 3.0d, 2" suspension lift, 235/85/16 Cooper STT Pros. 217k hard miles

[diggerdave]

BTW, is your diff an R16?
_________________
1997 KZJ90 3.0d, 2" suspension lift, 235/85/16 Cooper STT Pros. 217k hard miles

[mike adams]

Dave
I am running 255/75/16 on the 7jj alloy rims.
My rev counter is showing about the same.
215/85/16      95.43 circumference
255/75/16     97.52
265/75/16     99.41
When I got the LC I took the axles off, needle gunned and painted them as they were rusty  so I don't have any stickers left.
I think there were different ratios on the auto which most were.I think you can check by jacking one wheel and turning the prop shaft and counting the revs on the free wheel. I think this goes twice the ratio.
Seems like it would be happy with about 2300rpm at 70 but that is just a gut feeling.
I will check when I get a chance.
Regards
Mike

[diggerdave]

I am 90% sure that the OE small-tyred versions had the 4.1:1 diff ratios, from what little info is out there on forums.  

After all, I think it makes sense; larger tyres=more inertia/drag=need a lower gear (4.3:1) to get them moving, smaller tyres can be rotated with a higher gear (4.1:1) all other things being equal (have I understood diff ratios correctly?).  

In practice, the higher ratio diffs have no problem shifting my 265/75/16 tyres, but I dare say a car with lower diff ratios would be marginally quicker off the line.

I'd be interested to know if automatics came with 4.1:1 diffs as that would open up my buying options considerably! Anyone?

THis is really a short cut.  I know the only way to be certain is to open the diff and count the ring gear vs. pinion teeth.  I'm not even sure that jacking up a wheel and counting the turns would be accurate enough to distinguish what seem to be very similar ratios, at least not when executed by someone as ham-fisted and inexperienced in these things as me
_________________
1997 KZJ90 3.0d, 2" suspension lift, 235/85/16 Cooper STT Pros. 217k hard miles

[diggerdave]

Anyone please?
_________________
1997 KZJ90 3.0d, 2" suspension lift, 235/85/16 Cooper STT Pros. 217k hard miles

[diggerdave]

Just a quick update on this:  I've double-checked my R16 diff and it is definitely 4.1:1

Still none the wiser on the other codes though.
_________________
1997 KZJ90 3.0d, 2" suspension lift, 235/85/16 Cooper STT Pros. 217k hard miles

[poze]

Here you have two versions http://www.toyodiy.com/parts/p_E_1997_TOYOTA_LAND+CRUISER_KZJ95L-GKMNTW_4101.html

43:10 for automatic
41:10 for manual

[poze]

Other codes can be for LSD models.

[diggerdave]

Thanks Poze, that's really useful info.

As stated on the other thread, I think I've sorted my replacement diff (test drive tomorrow) now but hopefully this thread might be of  use to anyone with the same problem
_________________
1997 KZJ90 3.0d, 2" suspension lift, 235/85/16 Cooper STT Pros. 217k hard miles