Outer Limits 4x4 Board

My friend who is a new member to this forum is wondering about the width and ratio's etc of F100 diffs for use in a 4.2TD GU Patrol.

He has some diff noise but apparently it is probably nothing serious etc but an excuse to do a swap like this wouldn't go astray eh

Has it been done, is it any harder to do than say Hilux diffs under a zook or Nissan diffs under a Hilux???

Any advice certainly welcome

Why would you bother when GU diffs are allready plenty strong enough.

exactly why would u bother

GU diffs are the most popular as they are the strongest diffs around

some guys in comp havnt smashed anything yet and there diffs arent even laminated.

id recomend he does the swap,

id also recomend him letting me know how much he wants for the GU items,

this would be his bestplan to follow,

ozy1 wrote:id recomend he does the swap,

id also recomend him letting me know how much he wants for the GU items,

this would be his bestplan to follow,

hahahaha

I'll go to the dump and find some crusty F100 diffs with drum brakes and swap your mate for his GU stuff so I can sell it .

Fair enough guys, your opinions have been noted.


Now then, anyone have some real answers??? Width and lower gearing is the plan and just because no-one has done it doesn't mean it cant be done and wont have more strength. After all the F100 is pushing a 7LTR twin turbo or some shite like that isn't it? Gotta be bigger

high n mighty wrote:Fair enough guys, your opinions have been noted.


Now then, anyone have some real answers??? Width and lower gearing is the plan and just because no-one has done it doesn't mean it cant be done and wont have more strength. After all the F100 is pushing a 7LTR twin turbo or some shite like that isn't it? Gotta be bigger

Most comp cars are puttin out shit loads more power and torque than a F100 and the diffs stand up to it.

So you wouldn't want the extra width then??? And you know what a F100 diff will stand up to??

Anyone with serious answer please contribute, I know GU diffs are strong but geez, Effies have to be better or atleast equal.


All I need of I'm getting no well informed answers is the ratios and if the steering setup is completely different etc.


There is always a first

The physical size of even the GQ/GU diffs is too big sometimes, Think of the tyres you would need, just to get the same clearance as the stock Patrols.

On 35's atm so clearance wont be a huge issue

they wouldn't be as strong as a GU diff i reckon ... i'd compare them to GQ diffs
lots wider tho ... if he wants to be different yeh sure why not ...
don't thinkt he extra width is going to help u tho


if he does it i want the GU diffs

auction on the GU diffs then, who wants first bid

$2.95! would u like fries with that

Hoonz wrote:$2.95! would u like fries with that

Even with an apple pie it still wont get you those diffs

Are we talking new or Old F truck?

It all depends on what F series you are loking at. GU diffs will be larger and about the same width as most F 100's. Also F 100's from the 80's onwards have an independent front end (look under a bronco and you will see what i mean). If you go bigger, i.e. late model F 350 without dual rear wheels, the axels will be alittle wider and bigger. You will probably get full floaters in the rear into the bargin. The rear is called a sterling and has a 10.25 in ring gear. They have 35 to 40 spline axles. The fronts are usually a DANA 44 or 50. The 44 has a 8.5 inch ring the 50 has a 9 in ring in a DANA 60 housing. Both have 30 spline axles. The Dana 60 which is found in the front of the Dodge RAM has a 9.75 ring and 35 spline axles. These are just some of the combinations available that I have found whilst bored on an overseas trip. There are heaps more! As far as diff ratios go, what do you want. The DANA 50 goes up to 5.13 the rest of them go to 7. 28 or somthing stupid like that!

If you want big and wide axles, try get some out of an OKA. They use a DANA 60 in the front and a Corpral 14 bolt in the rear I think. They are as big as a Sterling or DANA 70, but GM's version.

I beleive we are talking newish here. disc all round etc....

high n mighty wrote:So you wouldn't want the extra width then??? And you know what a F100 diff will stand up to??

Anyone with serious answer please contribute, I know GU diffs are strong but geez, Effies have to be better or atleast equal.


All I need of I'm getting no well informed answers is the ratios and if the steering setup is completely different etc.


There is always a first

OK, I will try and give you an unbiased opinion. I have an F150 (same as F100), the rear 9" is a 31spline version, and is probably similar strength to the GU diff, if not a little stronger, due to what I think is better materials. Other's may have different opinions. weaknesses are in the LSD hat, and axle bearing retainer plates. both items are available for about $100 in stronger steel versions. obviously gears and lockers, stronger axles etc are all too easy and extremely cheap to get. the most you will pay for ratios is $300, 31, 33 or 35 spline alloy axles are $900 including thicker retainer plates, and 11/16 wheel studs, some with a lifetime guarantee.

in saying this, i have pulled out my 9", and am selling it, as i have installed a Corporate GM 14 bolt full floater diff. Much heavier, bulkier, and stronger. and quite cheap.

The front diff is a dana 44, quite strong, good for about 33 - 35" tyres, still quite cheap for ratios and lockers, can buy stronger axles straight from the states. I doubt they will be as strong as the nissan unit. I have kept mine, but am looking at getting a dana 60 in the future, probably what you should be looking at.

all said and done, i wouldn't change what you have, you already have the strength, maybe get a h260 (big nissan GU diff in some coil cab utes) and maybe some stronger birfields.

I dont think my 9" is much longer than a GU diff. maybe get some spacers or something. if you want my 9", it is 3.5 ratio, 31 sp, and i want $700 for it, can post anywhere.

Don't kow if the OKA has discs or not. Never looked behind the wheels!

call up southern 4x4 recyle in melbourn they want $2700 for GU diff housing front only

if thats not saying then what is....

most serious competitors are running GU gear even in toyota and GQ as well and rangie for that matter

So what you are sayng is that F100 hasn't been tried???? People are sticking with GU cause everyone has done it????

come on, someone must know specs and not bullshit.....


Crush-U and Cookie monster, you have both been a great help

Why not go for some portal axles?

From my limited knowledge I know the diff centers in the 9" could probably be built stronger than any GU diff thanks to the many drag racers that use them. I have no idea about what the cv's etc are like in the F-truck.

It sounds like your mate has some money to throw around if he's changing GU axles so he should get some cutom axles like this made up

http://www.sunrayengineering.com/1550.html

A more realistic option would be the 9" center with d-60 steering assembly. Wouldn't mind doing this but the legalities are probably a bitch and the $$$ involved I imgaine would be quite large.

The Nissan GQ/GU wagon rear axles are 37spline and about 1.5" - in other words bloody strong - they are semi-floaters though so that weakens them a bit. I have never heard of anyone who has broken one of these things, and I have seen plenty of people drop the clutch at 3000 rpm in 1st low and launch up hills on 36's.

The ford 9" (F100 rear diff) is very strong as well, but the standard (non nodular iron) diff housing is crap, and nodular cases are expensive aftermarket. As Crushu said, they only come stock with 31 spline axles. IMO a Nissan rear would be a lot stronger than a ford 9". Sure they are run by a lot of drag racers but those diffs have very expensive aftermarket components to keep them reliable. And work out how much torque a drag car produces and compare that to the torque output of a Nissan with a worked turbo diesel and 200:1 first low. If a drag car produces 1000Nm at the flywheel, has a 4:1 first gear and a 4:1 diff ratio, that equals 16000Nm at the wheels. A Nissan that produces 500Nm at the flywheel, has a 4:1 first gear, 4:1 diffs, and 3:1 T-case gears, is already producing 24000Nm, far more than the drag car. (and that is only at 48:1 reduction, many trucks have a lot more).

Any anyone who pulls out a Nissan front end and fits a Stock D44 has rocks in their head.

But if you have lots of money and want to swap the nissan diffs for 35 spline full float D60's front and rear, then there may be some benefits.

If he can find a d60 front diff from a late model F truck (not sure if the aussie versions come with these - aparantly this was an aption in the US) then he would be way stronger than a GU front.

Carnt believe people think the GU is the be all and end all of front diffs.

Sam

think the current models of ftrucks in au are running a d60 front end and d70 rear
will check tomorrow

dana 60s in the okas come with disc brakes in the front, dont no for sure if these units were made in the u.s.a but due to cost cutting with oka nearly the whole vehicle was made in india, so im pretty sure most of the parts were aswell.

bazooked wrote:dana 60s in the okas come with disc brakes in the front, dont no for sure if these units were made in the u.s.a but due to cost cutting with oka nearly the whole vehicle was made in india, so im pretty sure most of the parts were aswell.

The OKA's have a D70 rear (the early ones may have had a D60 rear though).

So what you are sayng is that F100 hasn't been tried???? People are sticking with GU cause everyone has done it????

come on, someone must know specs and not bullshit.....

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But why would anyone change them for no reason, if there hasnt been any major problems?
I dont understand your logic?

Bazzle