Anyone know if the ordinary and LSD diffs are the same size externaly?
Almost.
They share the same 7" mounts (assuming you are talking the XR4x4 LSD), but the sides are obviously different for the different driveshaft types.
i.e. an XR4x4 diff will swap with a standard diff without any problems, as long as you have the right driveshafts etc.. to go with it.
Cheers mate,wondered why the n/s hub nut was lht and all the others ive ever done are rht
Yeah, that's a 4be4 alright.
I wondered that too - after breaking three Halfords professional breaker bars, and resorting to towing the thing to my local garage to get the n/s
rear nut off (yup I was tightening it).
Halfords lifetime gaurantee worked pretty well though...
Do you think it's worth using a LSD for a Fireblade engined car? Are the hubs different for a normal unit? i.e. Could I use normal brake disc hubs and
a standard diff and then swap to a LSD later just by changing the diff and drive shafts? I'm told that the diffs can't be mixed and matched between
dics and drums - is this the case?
Cheers,
Max
I would have thought you definately would be able to change the diff and shafts for an LSD later.
I cant imagine your disc hubs are any different to mine, and my sierra has the LSD and associated shafts already.
Liam
It is worth using an LSD (always), but the bits aren't interchangeable with each other. If you want to go from drums and an open diff, you need the
disc brake diff shafts, bearing carriers(hubs) discs and calipers, so yes, in this case they can't be mixed between discs and drums.
But if you have discs up the back anyway, the LSD comes free with the rest of it, so why bother swapping?
Are the ratios between the standard and LSD Sierra diff the same?
Cheers,
James
Depends, there is so bleeding many of them. Ford didn't have rules on what got fitted with what it seems.
As they stand, the XR4x4 V6 and the Granada 4x4 V6 have 3.62:1 LSD, the XR4i and the Granada V6 (non Scorpio) has a 3.36:1 open, and the Scorpio V6
has a 3.62:1 LSD
The Granadas get the 7.5" case, whilst the non-cosworth Sierras get 7"
Dave
My diff'n'discs came from a glsi sierra,so i was told anyway.
For some reason i was expecting LSD,but its just a regular diff with lobro joints unlike the tripod joints on the drum version.
Have no idea of the ratio and fords were not much help on this either.
Any clues apart from counting teeth,tab on diff is unreadable like the engine number on me 1st engine 
yep, what you have is pretty standard of later Sierras. Discs=Lobro diffs.
There's a rule of thumb for spinnting the outputshaft and counting the prop roations, but it's a load of arse (can't remember it more like).
Flip the rear cover off and you'll find it stamped on the crownwheel 
Thanks dave
After finding an older haynes manual,which are much better than the shite new ones.
the 2.0 inj was 3.92 for manual and 3.62 for auto,will have a look anyway.
cheers 
3.92 eh? Also found in the 1.6 estate, and favoured for bike engines and K series implants.
And don't you just hate the way the new Haynes' are printed on bog paper?
There is a very good reason their printed on bog paper,thats all the books are worth! 
Bah, if only 
Have you seen their price in Halfords? sixteen bloody quid they are
Managed to scrub the tab up on diff and its 3.92
No use for a V8 diff then
Glad you got the ratio ID sorted though
I dont think it was life threatening but i thought i should investigate this one.
Seems unless its 4x4 there were 3 ratios on regular sierras
2.0 carb auto was the odd one out at 3.38
everything else is 3.62 or 3.92
The estates are a mix according to the manual with 4 speeds getting the 3.92 and the 5 speed gets the 3.62
quote:
The estates are a mix according to the manual with 4 speeds getting the 3.92 and the 5 speed gets the 3.62
I'm just quoting from an old hanes manual,but i know what you mean i thought that myself
Ah!! blimey theres more
1.6 with 4 speed economy was 3.13
and 5 speed was 3.38
yeah strange.
Also there was a trailer package on the 1.6 and that was 3.77.
ofcourse it could all be a missprint
3.13 is, it should be 3.14 (also found on the 2.3 V6 ISTR?)
Ideal for a V8
If I could possibly drag this conversation back down to my ignorance level please...
Can I conclude that if you fit a diff with a numerically lower ratio you'll be reducing your top speed but increasing acceleration? Or have I got that
the wrong way round?
Presumably this also means your speedo and odometer will be out as well?
And, for a given speed you revs will be higher and therefore fuel comsumption will be worse?
Questions, questions....
Cheers,
James
Sounds right
A lower ratio (numerically higher) diff will make it lightening up through the box, make your speedo over-read, stunt your top speed, and degrade fuel
consumption (the engine spins the gearbox upto speed, but the diff is throwing away all those revoloutions, IYSWIM)
's like a fella that was going on at me that he had fitted a type 9 to his Xflow (didn't know what it had come from) and complained that he couldn't
pull away in first, and didn't have enough power to pull fourth. Wouldn't listen to advice either ('cos I was younger than him........anyway, I
digress)
Classic case of a short (numerically lower) diff. He fitted the four speeder back in the end, for want of another diff
Take it from uncle Fatboy, know what you have and know what you need.
So I take it you're not in favour then!
quote:
Take it from uncle Fatboy, know what you have and know what you need.
It can be compensated for, but it means changing the tyre size by 8% (smaller I think). It doesn't have to be spot on, be near will do. Plenty of
people use the 3.62 without any problems, and 8% will be A-OK if you're changine the wheel and tyre sizes anyway.
Don't worry about it, just fit it. Either that, or get your bracket down to a scrap yard, and start peering under later Sierras.
quote:
get your bracket down to a scrap yard, and start peering under later Sierras.
Well now, Sierras are getting thin on the ground, and it doesn't help that scrap prices are so low most are going to the crusher, but there's a few abandonned ones around, and I'm in the middle of asking my local council if I can help myself (the wrecked ones go straight to the crushers....)
Yep,James is dead right about the prices down here.
I got my diff from Rotherham,it was a 340 mile round trip in ht efirms tranny and it was dtill cheaper with the 40 quids worth of diseasal i had to
put in .
Blimey. Where d' you live then? I'm in Hampshire (right at the bottom), I paid #80 private for an XR4x4 back end, #25 for a pair of uprights from a Sierra (complete, from a yard), a 10er or a column (Sierra again)........
Dave
£150 was the cheapest rear with discs,and when i wanted uprights and rack for the exchange with MK it was £80.
I got the uprights and rack from a breakers in doncaster for £55 delivered to my door the next day.
By the way i'm a few miles south of Heathrow airport.
There are some good breakers around here but they make you pay
Ouch!
If you have a look in my garage, you'd have a fit. I've been stockpiling Sierra bits for yonks. It's like my local breakers' storage shed
What you need to do, is live in Geordie land. We have this knack of being able to find rusty old Fords
I managed to get a MOT failure Sierra for £30 and drive it home. It took a few weeks of trawling the free ad papers but it paid off in the end.
Someone I know just paid £50 for the same thing. I started to take the wee for him paying £20 more than I did until he mentioned that it also came
with a spare 2.0L Cossie engine. I'm gutted
For the sort of prices you mention Bob you'd be better off buying a complete MOT failure, taking the bits you need and scrapping the rest.
quote:
For the sort of prices you mention Bob you'd be better off buying a complete MOT failure, taking the bits you need and scrapping the rest.
Ive got all the bits sitting in a box,lsd,calipers,shafts,nuts n bolts,£100 for the lot.Bargain i,d say!
Ring your local council and ask if they dispose of cars, a few do, its cheaper than getting shut of dumped cars once they've been burned-out...
Thought of that, mine doesn't
John
I've since had 2 sierras for £20 a time,local dealer can find em no probs.
The reason i had to pay for front hubs and steering rack was because chassis was ready to be picked up from MKs and i needed to exchange bits.
Rear diff's with discs are just harder to find.
Needless to say,as soon as i'd picked up the chassis the two sierras turned up.
Like they say,you cant beat bad luck