Blown Cressida Diff

[V8Cressida]

No, I didn't blow my diff. I have a blown (1UZ) Cressida and it would appear that I need to pay attention to my LSD. This is the source of all my troubles. A bit more power than normal...



My Limited Slip Diff...isn't limiting the slip. I left a nice long SINGLE black line the other day with my left (passenger side) wheel. Certainly looked different and has a few people a bit puzzled which is amusing. I was the only one in the car and the surface was good. I rang a diff guy and he said to jack up the car and have a buddy hold one wheel while I try to turn the other. It was fairly easy. It didn't seem to have much resistance though both wheels spun in the same direction so something's going on back there - just not enough of it.

I also have another 4.11:1 center (purchased from "Leon" on ebay) so I had my buddy hold the one flange still while I tried to turn the other. It also seemed to have some resistance but still turned relatively easily so I took it to my sports car mechanic across the road and he said he'd have a look. These things are bloody heavy! What size is the ring gear? I had a rough outer measurement and I'd say it'd struggle to be 7.5 inches.

Anyway, he did some research and said that these limited slip diffs are really "semi-LSD" only and will "let go" with too much power or under extreme conditions. Extreme?! Lol, I haven't even started yet! He had a look inside and said that there was nothing wrong with the 4.11:1 at all. It all looked good inside (Leon said it was rebuilt just recently - an honest ebayer - whoulda thunk it?!) and so I'll get him to install it and then take a look inside this one.

The 4.11:1 is only 5.6% lower than the 3.89:1 which translates to the speedo saying 65 when I'm only doing 60 - clearly a good thing. At 100kmh the engine spins at about 3,000. With the 4.1:1 it's about 3,300 - right on the power. Economy be damned (my other car is a 1966 19' long Buick Electra with a 401ci dual carbed big block Nailhead) I'll have too much pickup which is just right. I would also however like to try a higher gear but not sure if there is one.

So, what I want to hear from you guys about is everything about my diff. Here is what Michael Smith (original builder) said about it...

...I was initially attempting to source a LSD from a wrecked MX83 Cressida "Grande". Unfortunately, these are rather thin on the ground. The next option was to source a diff from an MA70 Supra, if it would bolt-in to the car. I had this particular item lined up and at this point I should give the blokes at Toyospares a bit of a plug.

I think that Toyospares are a bit expensive; I'll say that straight off the bat. However, while there are cheaper alternatives out there, these guys know their stuff when it comes to import bits and pieces.

Anyway the LSD was ready to go, and I'd already transferred the money to Toyospares' account. I got a call from Matt saying that there was a problem. (I'm thinking "O.K, here goes..."). He says "I thought they were identical, but, on closer inspection, the mounting points on the two carriers are just different enough to preclude a straight swap". (At least he thought to check PRIOR to shipment!). I basically told him to "find me a solution" and, about an hour later, he calls me back saying that they've sourced a dead MX83 diff from another wrecker and are going to transfer the LSD internals into that, making an effective "Grande" LSD.

That's what I call service! (For those wondering if this "swap" is feasible, I had another call from Toyospares this afternoon, advising that they had swapped the parts and were shipping the components...)

...so it would appear that I have a Cressida housing with MA90 internals (is that what Grande LSD diffs are?) so my question is...what is inside these LSDs? What type of LSD are they? Can they be rebuilt or adjusted? What are my options? What type of oil should I use? What type of oil should I NOT use? What gear sets or gear changing optionsare available? What other cars did these diffs come in? What parts are interchangeable? Mechanic said that a rebuild will cost about $1200 and it still won't work as an LSD with my power. Surely you turbo guys put more power into these diffs than I do? How much can these things take? Is there a specific weak point? Are there any mods I can do to strengthen it? What is the weakest link behind the trans. I'd prefer to have the tyres let go before I break anything (uni joints, diff...etc)

Big American diffs are easy. These tough little "import" diffs are all new to me. If anyone would care to educate me as to my choices here (or point me to a thread?) I'd appreciate it. How does 'Mr 747' get dual traction with his? Doesn't he use a stock-type diff in his MX83? Inquiring minds want to know. I'm all ears.

[wilbo666]

Just some quick notes:

MX83 is 8" ring gear.

Clutch Type LSD Stock.

Shane (1jz 747) runs a spool if I'm correct?

You should be able to get a TruTrac torsen LSD that fits

Cheers
Wilbo

[japlish]

for $1200 i'd be looking at getting an aftermarket '1-WAY' lsd. The grande ones, even when rebuilt aren't the best when it comes to power.
my 2 cents.

[amichie]

A number of people on the cressida forum have had their diff rebuilt with new clutches and found them to be heaps less slip.

If you want to change ratios by just 5 % just get different size tyres.

[IN 05 NT]

you can have the factory one rebuilt and have the clutches shimmed up, so they will LOCK alot quicker, make it tighter, will cost about the $500 mark to have that done,

weve got an LSD in our cressy, it will single spin maybe 1 in 5 wheely's
but its just a tow car/daily...lol

blake

[V8Cressida]

you can have the factory one rebuilt and have the clutches shimmed up, so they will LOCK a lot quicker, make it tighter, will cost about the $500 mark to have that done,

That sounds like what I need. Who does that work? Is it something my mechanic will be able to do or does it require special diff tools?

You should be able to get a TruTrac torsen LSD that fits

Sounds interesting. Where would I start to look for one of those? Do they come in a car as standard or are the race items?

A number of people on the Cressida forum have had their diff rebuilt with new clutches and found them to be heaps less slip.

If you want to change ratios by just 5 % just get different size tyres.

By heaps less slip, do you mean they worked better and tighter or were worse?

The reason I bought the 4.11:1 was...it was for sale. I wasn't actually looking for an extra 5%.





Just got back from across the road and took these pictures (above) of the diff that was in the car when I bought it (3.89:1 LSD Supra in standard MX83 case) and my mechanic says two things.

1. The centre is very different to "Leon's" 4.11:1 ebay rebuilt LSD
2. It's not an LSD
3. We've just put the 4.11:1 diff in and he's grabbing both wheels and though if you spin one wheel the other spins in the same direction they have very little resistance against each other when spun in different directions.

Here are two pictures of the 3.89:1 LSD(?) that just came out of the car. My mechanic says it's not an LSD because he says you should barely be able to spin the wheels against each other. These almost free wheel (not quite but it's very easy). It's the same for the 4.11:1 I've got I'm replacing it with but the center in this one has shims and things (unfortunately, I didn't get to take a shot of that one - my bad, I'm spewing now). Anyway, it's got some new 80w EP (extreme pressure) oil in and we'll see tonight what's what.

Any input on what's going on would be appreciated.

[MWP]

Here are two pictures of the 3.89:1 LSD(?) that just came out of the car. My mechanic says it's not an LSD because he says you should barely be able to spin the wheels against each other.

Torsens wont lock without some torque (act like open at other times), and clutch pack LSD can wear out.
Just because he can do that, doesnt mean its not an LSD.

... im sure someone on here will tell you what that center is by looking at the photos.

[amichie]

By less slip I mean more like a LSD and less like an open diff.

[The Witzl]

Arent MA70 diffs Torsen, and not clutch pack LSD like the MX83 grande diffs?

Bill - a torsen diff uses gears to lock the two wheels spinning in the same direction, and a clutch pack LSD uses friction plates. A torsen can appear like an open diff, until you apply power, at which time the diff will provide equal power to both wheels.


Sorry, but i cant identify the diff in those pics.

[madmont]

Looks a lot like the lsd that I took out of my MX83 when I put in the Torsen
The clutch pack was assembled in such a way as to give more slip. A few of the driving elements were assembled together as were some of the driven ones. A bit like having a single plate clutch instead of a triple plate cutch. An aftermarket Hilux lsd will not fit this housing. You will need JZA70 torsen axles if you want to put in a Torsen

JZA70 Torsen

[JustCallMeOrlando]

One vote here for a Truetrac Torsen diff Bill. Given what you do with your car, wanting to enjoy it on the street, that'd be my pick, quite reasonably priced and don't wear out like a clutch LSD.

[Norbie]

I concur, TrueTrac FTW.

The factory clutch-type LSD's aren't that flash, even if you shim the clutches to buggery, and they tend to wear the clutches quickly when you're putting a bit of power through them. IMO your options are either (1) aftermarket clutch LSD (I believe there are a few different ones available) or (2) TrueTrac torsen LSD. The latter is cheaper and in many ways more street-friendly, not to mention it has no wear components, so it gets my vote.

Witzl: only the JZA70 got the torsen from the factory and it's known to be fairly weak. All other MkIII's got a clutch LSD like the Grande.

[V8Cressida]

Ok, now we're getting somewhere. Thanks everyone

How do I get my hands on one of these TrueTrac Torsen LSDs? How much are they and what's involved in fitting it to my MX83 housing?

[PlacentaJuan]

my stock lsd has held up fine, i serviced it once i put the new engine in and it has been sweet.

im sure if i increase the traction i will start seeing some failures ie driveshaft, diff and diff cradle, but at the oment the wheels are happy to spin and has held the 241rwkw fine.

i will get the ma70 torsen next time though....

[MR 1JZ]

Bill the pictures you have there are of an LSD diff..I know becuase I pulled mine out and had it welded last week

dont get a torsen...you will break it...

Cusco make a 1 way LSD which will suit your needs fine, you wont break it and I highly doubt you will wear it out anytime in the next ten years...do it once and do it properly...