faster diffs for a hzj75 ute??

[cheeckyboy31]

hey there folks, does anybody know if the diff centres out of a 80 series wagon will fit into hzj75 ute diff housings? are they the reason for the taller overall gearing or is it in the gearbox?
thanks

 

[Tapage]

It depends ..

All toyota - t-cases are 1:1 Hi range .. and most of the 5th are around .84 range ..

80 series are usually 4.11 but a few ones come 4.30 ( and 105 sure ) that have a rear 9.5 FF and 8" HP reverse cut ..

If you 75 it's newer could fit .. but gotta replace 4.11 with 4.11 ..

If you have the old front axle low pinion and 9.5 you can swap from a 60 series that come with 3.70 as mine ..

 

[crushers]

yes, they will fit if your ute is between 90 and 98 and the donor is the same.

BUT

they both are 4.11...no?

 

[cheeckyboy31]

thanks for that, i am just looking for taller gearing, IF my ute has 4.11 gears std and so do the 80 series, why do the 80 series cruise at 100km per hour at less rpm than my ute?(both having the exact same tyres) could i swap the ring gear and pinion into my pumpkins, i have the high pinion front diff-8.5 i guess? i have the genuine toyota manuals, they are good for doing the work but not so good for general info, like the stroke of the engine, you don't need to measure it for a rebuild so they don't tell you (its 100mm), maybe the 60 series ring gear and pinion will fit onto my centres?

 

[crushers]

60 series has full size front diff, yours has baby front diff

 

[cheeckyboy31]

ok thanks, now that you mention it, i do remember talking to a guy who had done some off road racing and said the cruiser front diff was the same as a hilux, and that they bend much more easily than a nissan pootrol.

 

[roscoFJ73]

thanks for that, i am just looking for taller gearing, IF my ute has 4.11 gears std and so do the 80 series, why do the 80 series cruise at 100km per hour at less rpm than my ute?

They have a different gearbox and slightly different ratio. The later model 80 series had a 4.3 diff. according to Slee Offroad

 

[cheeckyboy31]

ok, i have done a bit of web searching from the info you folks have provided and i think i have an answer,

front diff is compatable with hilux and i could get a 3.7:1 gearset

rear diff is compatable with 60 series, 9.5" also can get 3.7:1 gears

that just leaves the speedo, is it a matter of swapping the drive gear like an old ford or is this an electronic adjustment?

 

[crushers]

dude, you amaze me. seriously i am impressed. your like a blood hound after the elusive rabbit but in your case it sounds like you scored.
congrates, let us all know how it works out as i am interested in the same swap.

as for the speedo it is a nylon direct drive (no elec) and you can order the specific drive from Toyota to match your tires and gearing for an accurate speedo...

once again ... nice job "Sherlock".

 

[roscoFJ73]

that just leaves the speedo, is it a matter of swapping the drive gear like an old ford or is this an electronic adjustment?

There are gadgets that plug into your speedo cable and you can calibrate it to send the correct speed to the speedo .
You just need a GPS to get an accurate speed reading

 

[cheeckyboy31]

thank you both for the input, if i can get the right gear for the cable i will leave the electric stuff go but handy to know.

there is also a front diff with an electric locking mechanism, not yet sure what other circuitry is required to drive it but i am more interested in clean horsepower than a diff lock. none the less it is an option if it comes around at the right price.

 

[cheeckyboy31]

the gear swap in the diff should produce about 250rpm engine speed drop at 100km per hour based on my approximate calculations...2500x3.7/4.11=...
might be good to know if the gearbox swap will be possible 1, and 2 more cost effective, i have a H55F trans, genuine manual does not indicate ratios in the box or if a 80 series one will fit without problem. diff code on the tag is K085 which i believe is 9.5", 4.11, LSD 4pin is this right?...all the info for the diff came off american sites dealing with hilux/pickup and tacoma vehicles.

 

[crushers]

which "should" equal, quieter engine, better fuel economy, higher top speed.

that would make for a more enjoyable highway cruiser...

cheers and thanks for posting up the thread.

 

[lshobie]

I am not sure where you are located, but I have a third member wih 3.73's if you want it.

PM me if interested.

 

[roscoFJ73]

the gear swap in the diff should produce about 250rpm engine speed drop at 100km per hour based on my approximate calculations...2500x3.7/4.11=...
might be good to know if the gearbox swap will be possible 1, and 2 more cost effective, i have a H55F trans, genuine manual does not indicate ratios in the box or if a 80 series one will fit without problem. diff code on the tag is K085 which i believe is 9.5", 4.11, LSD 4pin is this right?...all the info for the diff came off american sites dealing with hilux/pickup and tacoma vehicles.

This is a better site more dedicated to cruiser specs.
http://www.cruiserfaq.com/00-00.html

An 80 series gearbox will fit as long as you have the clutch bellhousing and flywheel.
I think the 80 has a bigger clutch diameter(or at least the turbo and petrol versions do)

 

[cheeckyboy31]

thanks ishobie but i am in brisbane australia, thanks also to rosco and crushers for the info

 

[matt 105]

Gday
At some stage, out P.C.s (troopys) had different diffs to our utes, and so went faster, or pulled less RPM.- Is this the way your wanting to go?
Those P.C.s had disk brake rear - so does that make them 93 on?
Might make it easy
Also, I thought a STD 80srs had a different ratio diff to a GXL.
Sorry, I never took much notice.

Matt

 

[Tapage]

I keep one of my R&P set at home .. 3.70 9.5"

 

[Letsgomoreplaces]

75 series diff

60 series has full size front diff, yours has baby front diff

What year vehicle? Highpinion front diff? If it is high-pinion than it is the 8" diff (reverse cut) this is the same as found in 91-97 80 series front. Finding 3.70 for that diff is going to be real tough, never offered in north america. If it has the 9.5 front diff, its easy. We even stock new gears for these in 3.70 or fj60s came with them as well. The rear is the 9.5" diff. It should be obvious, just take a look. Does the 3rd member up front look identicle to the rear, or does the driveshaft come in above axle centerline up front?

 

[cheeckyboy31]

i have a 1997 hzj75 ute. it has 9.5 rear and small high pin front. from what i have found the front diff is the same as an australian hilux ute, for which there are 3.7 gears. the intended solution for less rpm at 100k's is a 60 series rear and a hilux front to supply the gears (3.73)