ratio/diff help

hi guys ... ive got a 86 d/cab 4x4 with the vn v6 and t700..31" tyres.
at 100k's she revs at 2100 sounds like its about to take flight...

i think there 4.6 or 4.8 now ? ied like 4.11 or 3.9?

my question is what diff gears will fit the front diff ? and back diff ?

not 100% but been told the front 3.9 patrol gears will fit the back navara diff?

hi guys...
my id tag says:
FS5W71C HG46 = R180A front diff and H233B rear ?

quote i found on here..
"Use a 3.9 from an auto petrol Patrol for your rear H233B, and a 3.9 from a D21/D22 4x2 C200 rear diff in the front R200a."

so from that quote 3.9 patrol will fit my rear but i need to get a R200A front diff and put the 4x2 3.9 gears into it ??? that sound right ?

I am not 100% sure on it though.

Ford Maverick auto's ran 3.9 gears. Oh and GU TD42T and TB45E auto's run 3.9's aswell.

The spline counts are the same for the GQ and GU front diff to (H233B) Navara and R50 Pathfinder rear diff.

I was told ages ago why a guy who works for Nissan, that C200 and R200A ring and pinion are the same part number.

Ill have to confirm it with Nizzbits.

Its the front centre you need from the GU or GQ.

hey guys.

this is sorta along the same lines as my new found problem so ill post it here and get your ideas

i have a d21 td27 4x4.

i have just been driving around sitting on around the 100 to 110 ond get people racing past. i guessed it was just impatient people till my dad followed me and asked me if there was a reason i was going so slow.

now for me to be going 100 road speed i have to have 120 booked on the speedo! . its not healthy because thats about 3500 ish rpm and i have 265/70R16 tyres.

what the!

also turns out its a petrol to diesel conversion could that have something to do with it? petrol diffs maybe? .

whats the opinions on fixing it because i do high kays for work running between sites!!!!

Yeah mate, sounds like they mucked up the diff ratios in the conversion, I'm not knowledgeable enough to give your specifics, but that'll be the problem.

fst_38 said:

hey guys.

this is sorta along the same lines as my new found problem so ill post it here and get your ideas

i have a d21 td27 4x4.

i have just been driving around sitting on around the 100 to 110 ond get people racing past. i guessed it was just impatient people till my dad followed me and asked me if there was a reason i was going so slow.

now for me to be going 100 road speed i have to have 120 booked on the speedo! . its not healthy because thats about 3500 ish rpm and i have 265/70R16 tyres.

what the!

also turns out its a petrol to diesel conversion could that have something to do with it? petrol diffs maybe? .

whats the opinions on fixing it because i do high kays for work running between sites!!!!

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I highly recommend using a satellite navigation device with the current speed indicated (it's an option you can choose on many). If you don't have one, Aldi sell one for under $100 that uses the iGo8 software - it's not bad. You can display the vehicle's speed (accurate to 1%) in the corner of the map display.

As for your vehicle speed & revs ... a petrol engine is much more comfortable at higher revs than a diesel, the conversion should probably have been accompanied by a change in diffs.

The only other way to get more speed from the same RPM is to increase the wheel size, and you're already on large wheels so it's not an avenue I'd look at.

How did I miss this whole thread...

billy_bob said:

so from that quote 3.9 patrol will fit my rear but i need to get a R200A front diff and put the 4x2 3.9 gears into it ??? that sound right ?

Click to expand...

Yeah.

The R180 was fitted as a rear diff to a bunch of cars so a C&P from one of them might fit? Saves the changeover to the R200A.

fst_38 said:

now for me to be going 100 road speed i have to have 120 booked on the speedo! . its not healthy because thats about 3500 ish rpm and i have 265/70R16 tyres.

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3500RPM at 100 is normal for a TD27 on 4.8s. Mine does the same and when I pulled my TD27 out, it had two hundred and something thousand on it, still going strong, and now the QD32 is at around 400,000 and happy, still doing the same thing. The sound of it at such high revs is unpleasant but it doesn't do damage.

fst_38 said:

also turns out its a petrol to diesel conversion could that have something to do with it? petrol diffs maybe?

Click to expand...

More than likely the speedo gear in the transmission came with the engine/transmission combo, and came from a vehicle with a diff ratio of 4.6 or lower. You need a speedo gear to suit your diffs, which are 4.8, to make it read correctly.

fst_38 said:

whats the opinions on fixing it because i do high kays for work running between sites!!!!

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Stress less, fit some sound deadening to the cab if it's loud, and if it really bothers you, fit some big-ass tyres (33") to make the ratio taller. It's a gutless motor and if you fit taller diff ratios, you won't be able to tow heavy things from a stop as easily, and have you tried it offroad with the 4.8s?? Weapon.

Wish i had 4.8 diffs....

Leprechaun said:

Wish i had 4.8 diffs....

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Sheesh, what more do you want, solid front axle, coils all round, front locker... Quitcher whinin'!

well on my old boys navman says 101 kays when the dial says 120.

i have fairly big tyres but ill probs go 33's next time

yeah its often offroad going in and out of earth moving sites. . . im the only ute that has not needed pulling out as yet! .

more info or links ect to the speedo correction please guys.

fst_38 said:

more info or links ect to the speedo correction please guys.

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You can source the gears to suit 4.8:1 diff ratios either through wreckers, or send a pleasant email to Garry at [email protected] asking for his assistance.

They look like the red bit in this photo (red is 4.625:1 though... you want a different colour, might be grey, not sure):


Once you've got one, jump under the car and remove the bolt (10mm) holding the little plug in, just follow the speedo cable back to find it, pull the plug out and take the circlip off the end to change the gears over. If it's still out-of-spec, take your gauge unit into an instrument shop to be calibrated. Get the needles replaced while you're there since they all crumble away to dust eventually.

thanks dion.

as a side note after reinforcing and clearancing those control arms and new bump stops ( some conveyor belt ) there not chewing holes in my front shocks anymore . also the tyre shop fixed the wheels over problem with shims and a lazer line! . i just need a new steering damper but the 3 mobs work gets parts from, one being repco says there not a factory part so how do i chace another? 4x4xMore has nothing either. what make ect is yours

Good to hear you got those alignment problems sorted mate.

fst_38 said:

i just need a new steering damper but the 3 mobs work gets parts from, one being repco says there not a factory part so how do i chace another? 4x4xMore has nothing either. what make ect is yours

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Haven't got one. I don't see the need. I'm not sure where to get one from.

Hi guys, I also have a d21 which has had the naturally aspirated 2.7D replaced with a td27. My trans axle code says FS5W71C CA48, and the highway revs lead me to believe that the diffs are the 4.8's. The transmission has TD stamped on the left side in bold letters, so I'm hoping it's the correct match to the turbo diesel. I have 2 major things on my wish list, finding a set of 4.3's to drop the revs at 100km/h and finding an intercooler (wrong section so I'll shut up about that).. Cheers in advance