I've got a '95 Longreach Ute with the optional Outback Pak,and was wondering if anyone has encountered problems with the 3.45:1 ratio BTR Engineering LSD diff.I thought the problem was due to a change in tyres.I went from a set of Firestone ASR's(originally fitted to XH Outback's)to a set of TOYO Open Country tyres,and thought that the tyres were too soft a compound.
I'm getting a lot of what sounds like loud "clunking"? noises as well as tyre squealing and thought it was due to the chunky style of tread.The noises/tyre squealing only occur when making RH or LH turns,or on reversing out of of my driveway,and driving off.
Is there anyway,short of pulling the diff to check things out?,as the Ford workshop manuals,both the XF and the XG supplementary manual,have no reference to the Hydratrak diff,only the old style
cone clutch type LSD.Any thoughts or ideas welcome.

Cheers,
Kev.

If you haven't already, change the diff oil, if you don't know when it's been changed last.
Then give it a work out with lots of turns, roundabouts, etc. Oil is same as LSD IIRC.

I had similar with my LSD - scraping noises round corners - oil change and time seemed to make them go away.

Other than what you've mentioned, that's probably about all you can do - you could put the handbrake on, get someone to engage reverse, and see how much pinion movement(tailshaft rotation)you have.

Did some of those outbacks get fitted with diff lockers?? Some random memory in my brain is suggesting they did..... maybe I an just thinking of the jacked up BA ute that Ford took to market a few years back??

Anyway, it sounds like the diff is exceedingly tight and not allowing the two wheels to rotate at different speeds when turning, as an LSD should.

I would jack up the rear of the car (one wheel at a time) and check the break out pressures on each wheel with a torque wrench by trying to turn the wheel off the ground. Start with low setting on the wrench and work your way up to the point where, either side of that point, the torque wrench does and then doesn't click out. Sort of like the price is right, if that makes any sense.

From memory, somwhere between 20 and 40 ft/Lbs is reasonable for a normal, up to tight, LSD. I am guessing that yours is going to be way over that.

Other than a tool to check the pre-load, this will not help you. But if it is high, at least you can eliminate other causes and just concentrate on the diff.

My first port of call if it is the diff and were a normal 'cone type' LSD would be an oil change with a friction modifier, but check first that the hydratrak unit is compatible.

Double post!!!

Last edited by philaddis on Sun Dec 06, 2009 6:46 pm, edited 1 time in total.

Hi snap,
I'll give the oil change and cornering/roundabout trick a go.The diff oil was changed just after the utes 1,500klm service(14 years ago),as the diff was making extremely loud banging noises,but only when making RH turns.Turned out to be a faulty LSD centre,and it was replaced under new car warranty
by Harrigan Ford.I jacked it up this morning to make sure the wheel nuts were tight(no problem there)and checked the uni's and crown wheel/pinion backlash,and those things seem to be O.K.I just hope it's nothing worse.
Hi philaddis,
I think the diff locker you're referring to was fitted the Ford RTV utes,both tray top and normal
bodied vehicles.This variant came out a few years ago after the XH Outback Pak option.I've seen both body styles running around near where I live.If I jack the whole ute at the back,and turn,say the drivers side rear wheel as if it was driving forward,the LHS rear wheel also turns in the same direction,ie;anti-clockwise looking at the wheel as if it was moving forward.I'll definitely try your idea of jacking the back up and leave one wheel on the ground and try turning the opposite wheel.
I think from memory when I was hassling Ford to fix the problem,I actually rang BTR Engineering up,and asked the about whether th diff should make any noises on cornering.
The bloke I spoke to said it shouldn't,as the internals were some sort of viscous clutch arrangement.But the first thing I'll do is change the oil as suggested by snap.
Thanks for you ideas,and I'll let you know how things workout.

Cheers,
Kev.

The Hydra-Trak diffs were crap. The viscous centres used to pack up. Same centres were used in the EL GT's, as well as the Holden GTS Commo's. Notice they didn't use them after EL???
They also had their own axle type too...had 2 different size splines on them. The smaller one went into the " Cassette "....the viscous centre bit.
I remember them being replaced under warranty...the cassette's.

Thanks for all the advice,much appreciated.Had to replace the whole diff as the Hydratrak carrier assy was R/S,and got a diff from an XH auto with a 3.23:1 ratio.Now I need to know what speedo driven gear(the one that drives the tacho/generator for the speedo)I need to get the speedo reading correctly.Rims are 15" with TOYO Open Country 205 series light truck tyres.

Cheers,
Kev.

Dose this help?

documents.php?d=30

Thanks for the specs page,much appreciated.

Cheers,
Kev.