My Hilux Diff. WTF?!

[Smokey228]

Okay, so i finally pulled my finger out and got stuck into the celica again.

My newest dilemma is;

I have two diffs, a 1410 and a 1400?! I suspected that i measured wrong as i never knew there was such thing as a 1400, so i used my 1410 axles and they are too long, by about 10mm. Im not 100% on the history of this diff, but im about 90% sure its not shortened.

a) Did a hilux ever come out with a 1400?

b) Is there anyone who will shorten hilux diffs and do a good job? would i get away with using 1370 axles, being that they'd be a few touches too short.
Or should i get some custom ones made and fork out that extra 1500$

c) Does anyone have or know some who has 1370 axles?

d) My last question was, did the 1370 come out with different drums than the 1410? Because im measuring 1400 with the same drums that i took off the 1410. ie. I have one set of drums but two housings. So i put them on the longer diff (1410) measured 1410, than swapped them onto the shorter diff (1400) and measured 1400.
Could it be the 1370s have slimmer drums than the 1410s? And if this is the case, please refer to questions b and c again

I have measurements from housing end to housing end, ie. where the drums back onto the diff. I havent got them on me, but am wondering what ppl with the 1410 measure and what ppl with the 1370 measure.

Cheers, and much love yo!
Jase

[Hen]

If your main problem (other than the confusion as to what it in fact is) is that your current axles are too long then just grind them down to suit. Most axles have around 10-15mm of spline that doesn't get engaged.

So if you cut 10mm off the end of the axle it should fit nicely.

Also with T series, you can run into issues of the factory open diff axles fouling on the LSD centre and needing to be trimmed. This may also happen with G. If of course you've fitted a different centre.

Hen

[merc-blue]

I think hen is on the right track, although i would get them cut off and cleaned up properly by a machinist

we have a goldtrack 9" in a car and a ratio (full nose) change means you need to swap the left hand axel, bizzare
just becasue 2 diffs are the same doesnt mean they are the same, they offen make more changes as production continues to fix possible weakness or other issues and compadability isnt always on there mind

[Smokey228]

Oh k. Sweet. That is exactly what i wanted to hear. lol

When i purchased the diff, i was told it was from a Hilux. But the guy told me alot of things that wernt entirely true.

So i might have to trim it anyway when i try to fit my LSD?
Anyone got a comparison between the LSD and Single axle lengths? Or even just a picture of both centers for a rough idea of how much would be trimmed for the LSD. That way i can atleast trim these down once and have them right or close to...

Still but, does anyone know about the 1370 drums vs' the 1410 drums? Are they the same width?


Cheers,
Jase

And just like that, +rep poped out of Smokey228's ass and climbed into merc-blue's and Hen's pocket. This was its new home. Atleast for now...

[MWP]

Still but, does anyone know about the 1370 drums vs' the 1410 drums? Are they the same width?

No idea, but a quick measurement of my RN25 diff gives 1200mm housing length.
Thats without the axles or hubs, so axle seal to axle seal.

[WDE_BDY]

Drum width won't change your overall width as long as they are seated properly, you will know straight away if the drums are too wide.

Callum

[Smokey228]

MWP, is yours a 1410 usualy than? Or a 1370? I think thats a bit longer than what i measured from seal to seal but ill have to confirm by measuring mine up!

WDE BDY, when i say drums i mean the brake assembly that bolts to the housing. If its bigger on the 1410 than it is on the 1370, than it'll explain why i measure 1400.

Basically what ive done is pulled the drum brake and axles all at once from the diff that measured 1410 from hub to hub stuck em into the dif that measured less from seal to seal and measured that one from hub to hub and got 1400.

So im kinda hoping that the 1410 drums brakes are like 15mm wider than the 1370 drum brakes

Either way though, im going to need to shorten these axles, ill talk to my machinist about taking 5mm off each. maybe like 7 for a bit of extra clearance. Just dont want to take to much. Im happy to take em to and from 3 times to get it right, but its gonna be a lot more of a c*nt if i have to replace em cause i took to much off

Cheers guys,
Jase

Ill get some pics up of this watts link, see what you guys think of the idea. Personally i like it, and it only seems to add like 10kgs, or there abouts.

+rep for those who have helped.

[rolleraction]

Hiace -v- Hilux G series axles often differ in length slightly (by about 6mm I thought) Henn has the right answer above.
Cheers

[Smokey228]

Some key words for ppl that might later search for these numbers?
Hilux rn25 diff axles G series

******************
Okay, so ive done some measurements.

The axles from hub face to end of spline are about 600mm
The axles have 50mm of spline, the centre has 35mm of spline. So i can confirm you can take off 15mm without losing anything significant.

Now with centre in and axles in, there was on passenger side, 4mm to much length. The drivers side was 8mm to long.

If i take 5 and 10 mm off, the excess axle length will push through and sit flush against the centre bolty bit again. So i could take 10mm off passanger and 15mm of driver, but to keep it easy i was thinking just taking 15mm off both anyway. Which would also keep it simple for the diff shops.

At same time ive decided to get them changed to 4 stud.

So now i gotta try find the ma70 brake upgrade and im thinking a LSD center. And the diff should be ready in a month or so!

Cheers for everyones help!
Jase

[WDE_BDY]

WDE BDY, when i say drums i mean the brake assembly that bolts to the housing. If its bigger on the 1410 than it is on the 1370, than it'll explain why i measure 1400.

Cheers guys,
Jase

What i meant was if the axle is seated properly in the housing then different drum width (assuming drum seats properly) has no impact, any extra width would be dealt with by the backing plate or the drum wont fit on the axle. You would soon know if the drums on one version were impacting on your width measurement as the axle would not seat properly or the drums would not sit on the axle properly.

Callum

[Hash_ra23]

At same time ive decided to get them changed to 4 stud.

I wanna do this too...but not sure bout legalities/engineerability..But i dont see why its much different to redrilling a volvo diff as many have done.

[Smokey228]

Ive heard of heaps of ppl doing this Hash, so i dont see it being much of a problem. It is gonna be something that needs engineering if you want it to be properly legal.

Id say take it to your engineer and ask him to recommend a place to have it done. If he says no, take it to your 'other' engineer and ask him to recommend a place to do it..

WDE BDY, that now makes sense Cheers, ill check out how the axles are seating. But what memory they were fine. Same with drums and backing plate.
When fitting these i made alot of assumptions and didnt take close notice of things that may not have been working properly. Mostly cause i was assured it was a hilux diff and it was going to be fine

Lesson number 1, dont take anyones word for anything. Its not worth the air consumed to make it. Check once, and check again.

Cheers,
Jase

[Big T]

There are hilux diffs that come in a 1400 width. The last diff i built was one and came from a 1992 4x4 Hilux diesel. Unfortunately i wasnt able to find out what specific model it was from.

Axle pcd can be changed and engineered provided they're done properly...



This used to be a 6 stud axle with a HUUUUGE 106mm centre-bore. It's now hubcentric to the disk being used at 67mm. The outer edge of the hub was also machined down to fit inside the rotor.

Eddie.

[Smokey228]

I measure the centre-bore to identify if it is the same diff. If it is, ill have to machine it down to 67mm to fit the ma70 upgrade than?

Cheers,
Jase

+rep rains from the skies above

[Big T]

Dunno about the ma70 disks... the ones pictured are r31 disks. You can find out by checking the DBA catalog though.

Eddie.