Help!! D40 Auto diff into a 6 speed manual

[c33benno]

Hey Guys

This is my first post onto this site new Navara owner here cant wait to start modifying!! So the Navara I bought has a broken rear diff and all it seems I have to replace it with nearish to home is automatic versions.

My question is will it all bolt in normal no modification and match up to the manual tailshaft?
How much different are the ratios from manual diff to auto? is it going to make massive differences?

Any help would be greatly appreciated

Cheers ben

 

[bods]

If its a 4wd and the ratios are different you will need to change the front diff to match. You will wreck the transfer case chain if you have different ratio gears front and rear and try to drive in 4wd on a dirt road or track. this is because the front and rear axles will be trying to turn at different speeds

 

[JPMC]

All the diff ratios are the same with it's 2wd or 4wd but the manauls run 3.692 where the autos run 3.538 then the 550's run 3.133.

Not sure about mating to the tail shaft but considering they only sell one UJ for the rear I'd say they would be the same.

And as said above if it's not matched to the front you'll run into problems. As well as the above you'll run into problems with the ECU as it monitors differences between front and back via ABS sensors and will light up the dash with a fault while in 4wd mode.

 

[mgermasi]

hope this can help

http://www.navara.asia/showthread.php?p=213129#post213129

Cheers

 

[c33benno]

Ahhhh excellent thank you heaps guys I shall continue my endeavour to find a manual diff cheers guys

 

[Aussie Frontier]

All the diff ratios are the same with it's 2wd or 4wd but the manauls run 3.692 where the autos run 3.538 then the 550's run 3.133.

Not sure about mating to the tail shaft but considering they only sell one UJ for the rear I'd say they would be the same.

And as said above if it's not matched to the front you'll run into problems. As well as the above you'll run into problems with the ECU as it monitors differences between front and back via ABS sensors and will light up the dash with a fault while in 4wd mode.

That will all depend on the year model you have
I have the 07 2wd and its a different ratio to the 07 4wd
in the later models the 2wd came in Diesel but in the earlier D40 the 2wd was Petrol only

 

[JPMC]

That will all depend on the year model you have
I have the 07 2wd and its a different ratio to the 07 4wd
in the later models the 2wd came in Diesel but in the earlier D40 the 2wd was Petrol only

Sorry I was just going off the latest models of which all are diesel here in NZ. Also it appears in the link above that the Aussie Thai built get different ratios to the Spain built yet here in NZ ours (Thai or Spain) are all the same it's just different between auto and manual as I stated.

 

[Aussie Frontier]

Sorry I was just going off the latest models of which all are diesel here in NZ. Also it appears in the link above that the Aussie Thai built get different ratios to the Spain built yet here in NZ ours (Thai or Spain) are all the same it's just different between auto and manual as I stated.

Dont forget that the different years are possibly place of manufacture. That chart is for the Gen I and Gen II D40 which only came from Spain. It was after that where the models came from Thailand as well.
Nissan spent 6 hours trying to work out what was wrong with my diff till they found some very small print somewhere that said the 4x2 is an open center. The diff ratios are all over the place as such.

 

[big zetor]

Spanish built rx's 4x4's had the same ratios as the auto 4x4's aswell not sure about the thai built rx's

 

[bods]

I guess it depends what's "broken" in it, if the crown wheel and pinion are OK then it may be a good excuse to put a locker of some sort in. If they are busted surely just getting them shouldn't be too hard...?

 

[c33benno]

Yeah I don't actually know what's broken it clunks whirs a bit and leaks I did consider a locker but I'm unsure of the issue so I was just going to replace the whole lot

 

[c33benno]

Btw it's an 08 rx 4x4

 

[big zetor]

just remember your ratio is (3.538) same as the manual rx's and different to the stx manual 6spd manual (3.692), when I got a near new diff put in my 06 rx 6spd it cost me $1000 for the stx rear diff and $500 for the stx front diff, I changed to stx diffs because I was running 33's. if you go this way you need to do both diffs or you will screw up your transfer case and you simply cant keep it on the road wilst in 4 wheel drive

 

[c33benno]

Hmmm mines a 6 speed manual rx.... Outta curiosity I prices up a brand new one 5669.54 hahaha part number is d3003-3x02d

 

[big zetor]

i got those diffs out of a wreck that only had 17000ks on it.

 

[bods]

Well the leak could be the front seal and the clunking and whirring could be because of low or wrong oil in there. I'd find out where it is leaking from, fix that and change the diff oil and see how it goes before you rip the whole thing out...

 

[c33benno]

Yeah it's looking like I might go this way anyway, no one can 100% tell me what ratio this diff is, I can't believe the manufacturer doesn't even know what they installed. It's a joke half the wreckers are saying no no it's definately a 3.692 others say 3.538 rang up to get an airlocker done still a 3 week wait so I need to buy something temporary its not just the whirring and the clunking it squeals and vibrates quite harsh

 

[Aussie Frontier]

Well you could always just unbolt the hat and drain it so you can count the teeth. It will tell you for sure what it is
48 teeth = 3.693
46 teeth = 3.538
Also means you might get an idea whats making all the noise.
Then you can just use some gasket silicon and seal the hat back on.At least you will know exactly what your looking for.

 

[big zetor]

it's 100% 3.538 mate but like aussie sais just drop the oil and take the back cover off and have a look at the crown wheel, jack it off the ground and spin it around look for metal pieces, it might not even be the diff you dont need to be a mechanic to do this' just make sure you have gasket gue when you bolt the cover back on. cheers

 

[bods]

as said above, its worth having a look at least. if you don't want to pull it apart then at least drop and change the oil and see what it looks like and if new oil makes any difference. for maybe $50 that the oil will cost that would be the first thing i'd try...