A Diff'Rant Tale...

[Mad Manny]

Steve's Auto Clinic - Centurion SAC:

As promised, the SAC story:

As mentioned, in 2014 we heard a horrible noise which we eventually diagnosed as the timing chain.
I had a mate at SAC Centurion & took it there. R2000.00 later all sorted.

Then in early 2015 we hear a similar noise - I called SAC, the said bring it in. They claimed the timing chain stretched but they'll adjust it.
Those who know motors, will know what I think of the 'stretched chain' diagnosis. It was clearly incorrectly installed.
Anyhoo, the fixed it - no charge. All good.

Then all hell broke loose. Big noise, steering stiff (no hydraulics to power steering, etc). It looked to us like the timing chain had either snapped or come loose.
SAC collected it on a trailer.

We were told a cog broke, but I remain 100% convinced that the chain SAC fitted either broke or came loose.
SAC took weeks to fit it & charged me a fortune to do so.
In fact, at one stage, I popped in, unexpected, to see what was going on & while showing me the motor & the (lack of) progress, the guy accidentally said "When the timing chain broke..." he then realised his slip up & said "Umm.., err... I mean, err... wa...when the cog broke".
There was also other evidence I was being lied to, like a feeder spout I was told was broken, but when I pitched up, unexpected, I noticed that the original feeder pipe was still in place - undamaged.
There are other examples too...

We got it back, but they had to cut a cross bar on the carrier in order to get the engine in, they clearly got a blind drunk to re-weld it. Disgusting work which we had to redo...

A few days later, my guys call me from Pretoria to say the engine over heated. I drive out. The top of the radiator is cracked.
Clearly damaged when they tried to get the engine in with that cross bar in the way - which explains why they cut it off.
They had obviously bashed the radiator when refitting the engine.
I inquired about this, but they assured me they only fitted the radiator after fitting the motor.
Either way, the radiator which had lasted 225000km, suddenly splits open within 800km of being removed (or bashed) by SAC.

All in all, from the day I first got it back from SAC after the initial timing chain replacement, SAC had the vehicle 3 times ('stretched chain, snapped chain & radiator) these 3 visits totaled over 30 days that my vehicle was off the road & cost me R12 000 to fix stuff SAC Centurion had broken.

I'd rather walk that ever take a vehicle to SAC again...

[Mad Manny]

Aha, so my advice wasn’t as bad as you made it out to be?

You were actually great Kurtie.

[BushWacker]

... reminds me of

Gone with the Wind
and
War and Peace

why didnt you put some other axle in there
like Pierre did ,..
or no diff like my little Corsa ?

[KurtG]

Manny, you went to the wrong Mitsubishi scrap yard..

The one I recommended is called Parthunt, not Parthunter [emoji6]

[grips]

Manny I think Gearmax stuffed up right from the start. I have stripped and repaired many a diff.

From your pics it is clear that the root clearance on the spider gear was not properly set right from the start. In plain simple language the gears were set to run on their tips only.

There is two sets of shims, thrust washers or spacers call them what you like. In most cases you set them with a shim or washer on the two spider gears of the side shafts. Shim goes in between the spider gear and the cage.
It is evident that the spider gears only ran on their tips, the reason why a poefter engine with no torque ruined them in the end.

They either neglected to fit the shims, or left out one, or never checked their clearances with wrong sized spacers or shims.

By the way Gearmax diffs are found in most SA pick up trucks and are spinoffs of Spicer and Dana. I have lost faith in Dana diffs. I was told they were super strong. Well, I have managed to break a side shaft and stripped the pinion on a Dana 44. Also, their seal arrangement is not the best. If you play in mud and water take the effort to strip and regrease the front bearings. They told me a Dana 60 is the Holy Grail.... well.... I broke a side shaft on that aswell

See the pic below the items red circled.

[Apocalypse]

Grips .

We all know that with sufficient force one can break one’s finger off in one’s own sphincter***







***Manny says I can’t use the word ‘arsehole’ on the forum.

[Apocalypse]

Manny I think Gearmax stuffed up tight from the start. I have stripped and repaired many a diff.

From your pics it is clear that the root clearance on the spider gear were not properly set right from the start. In plain simple langue the gears were set to run on their tips only. There is two sets of shims, thrust washers or spacers call the what you like. In most cases you set them with a shim or washer on the two spider gears of the side shafts. Shim goes in between the spider gear and the cage.
It is evident that the spider gears only run on their tips the reason why a poefter engine with no torque ruined them in the end.
the neither neglected to fit the shims or left out one or never checked their clearances with wrong sized spacers or shims.

By the way Gearmax diff`s are find in most SA pick up trucks and are spinoff`s of Spicer and Dana. I have lost faith in Dana diff`s. I were told they were super strong. Well I have managed to break a side shaft and stripped the pinion on a Dana 44. Also their seal arrangement not the best. If you play in mud and water take the effort to strip and regrease the front bearings. They told me a Dana 60 is the Holy Grail well I broke a side shaft on that aswell

See the pic below the items red circled.

just to add to that - if you take a look at the one gear the teeth on one side are unharmed while the other side is heavily beaten.

I'd suggest a bent half shaft - you can assemble a perfect diff, but if the shafts run eccentrically in the housings, it's not going to be long for the world.

Of course... this begs the question.... how the hell do you bend a half shaft with a motor that sh... sh.... oh wait. Manny says I can't use the word shit on the forum....

[Oppies3800]

Grips .

We all know that with sufficient force one can break one’s finger off in one’s own sphincter***







***Manny says I can’t use the word ‘arsehole’ on the forum.

How about asshole?

Sent from my SM-G920F using Tapatalk

[rudi.hinze]

Manny I think Gearmax stuffed up tight from the start. I have stripped and repaired many a diff.

From your pics it is clear that the root clearance on the spider gear were not properly set right from the start. In plain simple langue the gears were set to run on their tips only. There is two sets of shims, thrust washers or spacers call the what you like. In most cases you set them with a shim or washer on the two spider gears of the side shafts. Shim goes in between the spider gear and the cage.
It is evident that the spider gears only run on their tips the reason why a poefter engine with no torque ruined them in the end.
the neither neglected to fit the shims or left out one or never checked their clearances with wrong sized spacers or shims.

By the way Gearmax diff`s are find in most SA pick up trucks and are spinoff`s of Spicer and Dana. I have lost faith in Dana diff`s. I were told they were super strong. Well I have managed to break a side shaft and stripped the pinion on a Dana 44. Also their seal arrangement not the best. If you play in mud and water take the effort to strip and regrease the front bearings. They told me a Dana 60 is the Holy Grail well I broke a side shaft on that aswell

See the pic below the items red circled.

Not to question your knowledge oom Grips (I agree om the shimming of the spiders and side gears), but in relation to your Dana comments, I think it's unfair to base your opinion on failed components ( late 70's F250 diffs) which are over 40 years old, even if you rebuilt the diffs. Also, you get Dana 60's and Dana 60's. You in all likelihood had a 30 spline D60 rear.

Stick a 40 year old Cruiser diff (even rebuilt) under your standard (engine wise) V8 76 and put 35's on, you will break a Birfield joint also. Put the stroked small block in and you will break more things. Side shaft seals in both axles are nothing special from new. Add 40 years' wear and they leak. The Cruiser knuckle/ball may as well be open since it does not really keep water out. The drain plug also likes to get bashed off on rocks.

Please don't see this as me knocking the Cruiser. I have a number of Cruisers up to a new V8 Cruiser (and even an old J4 Cruiser with a D60 front and 14 bolt rear set up for 39's with a turbo'ed V8) and other vehicles with Dana and other axle types. I have broken side shafts in my older Cruisers and in a K10 and my Rubicon with 35" or bigger tyres with proper V8 power and/or low gearing and lockers. I accept it as a consequence of the changes and opportunity to upgrade.

Sent from my BV6800Pro using Tapatalk

[Mad Manny]

My Colt stripped it's OEM Gearmax Diff (twice), then a Hilux Diff - with what must be 48kW & 160Nm...

So I can well see a tuned V8 eating any other diff...

[grips]

Rudi in my defence I did not have Cruiser Diff`s in mind why I referred to diff breaking.
I do agree that the GM 14 bolt Diffs are king. In my opinion the strongest local diff`s are found in Patrols.
But even they are not equal as very few models came with the H260. Patroll guys rs are sort of shy to admit that they only have an H233 at the back [emoji38]

Back to the Dana`s: When I built the Yank Ranger I spent many hours researching diff`s. Reading many forums etc. I got the impression that they were instructable. Maybe it just my bad luck with them not living up to my expectations. Yes they are 40 years old but I carefully rebuild them - all seals and bearings get replaced etc.

When it comes to my 4x4'ing style I irritate the likes of my friends Manny and Quack (to name a few here on the forum). I go too slow according to them. The Dana 44 was not damaged where full power was applied. The side shaft snapped on the 60 - yes I did feed in the loud pedal but nothing extreme. But, for the 60, I will take the blame.

Attached is a video where I damaged the pinion on the Dana 44. You can built super strong Dana`s all the parts are available off the shelf, but that amounts to serious cash lay outs.

1.32 in the video

https://www.youtube.com/watch?v=f4uwA-BfzWU

[ThysleRoux]

As Apoc said - with enough force you can break off your finger in a dark bodily orifice.............. As a youngster, I managed to break the spider gears in the diff of a 1600 Ford Capri - TWICE in one day !!!

[Apocalypse]

Here Grips -

This is the Platform that the big ship lives on up at the studios.

This one shows 10 of the MANN Military spec reduction axles we used - we actually added 2 more for a total of 12 because the director decided the ship had to be longer at a very late stage,

Only 2 are driven, but they all steer.

Total package fully trimmed and wet is about 100ton.

The Motor is a ADE Air-cooled 6 as used by the military.... I don't know the power output and it probably lose a few along the way. but it makes about 300Nm just off idle which is nice for a 100ton ship.

First or reverse from the standard box - around 5:1 as I recall, sent through 3 Low Range Transfer Cases (also Samil stuff) with around 2,5:1

The Diffs themselves then have a reduction - around 2 :1 I think - before attacking the Driveshafts with all that multiplied torque - and then it hits the reduction hubs, another 2:1

so, 5 x 2,5 x 2,5 x 2,5 x 2 = 156:1 reduction at the half shafts.

It lives on a platform that has a 2 degree fall on it. The idea was it would never have to exceed 2 degrees or 1 km/h

Some genius decided in one of the later seasons they wanted to raise the nose, so they'd run it up a ramp of a few degrees.

They asked me If they should do it and I said no.

they decided to do it.

As it's only 'suspension' is the flex in the frame you can imagine the strain on items as they approached the ramp.

obviously, the centre pair of axles, the driven ones, lost a bit of load (still touched the ground while the front was 20m up the ramp mind you) which meant one of them spun up and then bit in.

The Drive shaft is a Solid steel shaft about 750mm long and as thick as your wrist.

When that beast snaps, it's like a large caliber rifle going off in your ear.

I was expecting it, and I still came close to pooing*** myself. the axle tube was dented and bent, the lower ball joint tore out. It was a mess and there was a lot of soiled underwear.

Power is Power. but torque can be multiplied

Which still doesn't explain how Manny's 2800 Colt managed to bend a side shaft!


*** Manny says we can't say 'kakked' on the forum.

[grips]

Nee Fok you built a 2wd 100t Carrier. .

But anyway it snapped shafts at 10km/h. You need some more wind in those sails Blerrie movie makers

But then Appoc I love your work.

[Apocalypse]

Nee Fok you built a 2wd 100t Carrier. .

But anyway it snapped shafts at 10km/h. You need some more wind in those sails Blerrie movie makers

But then Appoc I love your work.

It's a 4WD!!!