Jump to content
SAU Community

Recommended Posts

I've noticed this for a while now, when putting the power down around a corner, the car would rev a touch higher and would jerk around. I am not breaking traction, nor am I going sideways.

It almost feels like the clutch is slipping, but I've had that replaced about 1000km's ago with a ceramic plate jobbie, that fixed up old mr slippery-launch!

Now when driving, changing lanes while putting the power down, the car flicks-back into the other lane quickly, almost like I'm recovering from traction loss.... But i'm not.

I put the car up on jacks (the entire rear-end) and noticed how the wheels spinned when i turned them manually.

I can turn the wheels in any direction and the other wheel will follow suit SLOWER. I can also hold back one wheel while I turn the other. The drive shaft is still turning when I hold one wheel back.

It is obviously a touch stiffer when I hold one wheel back, but I can still turn it. I thought an LSD was supposed to force each wheel to turn the same etc ? and you can't hold it back ? (can you?)

I've recently replaced diff oil with Castrol LSX90 (the best stuff for LSDs apparently)

What is happening ?

What usually wears out on a diff to make this happen ?

How can it be fixed ? Can I just take it to a Differential specialist and tell him to weld it locked ?

Cheers Guys,

-Kym.

Link to comment
https://www.sau.com.au/forums/topic/15988-help-diff-problem/
Share on other sites

mine does the same, im not to sure what it is... just how it feels like your flicking the arse end out but u haven't broken traction in the first place. I have a feeling that it was something to do with the 4 wheel steer. Thats a guess, but thats what I was pointing towards

Sumo

Link to comment
https://www.sau.com.au/forums/topic/15988-help-diff-problem/#findComment-327751
Share on other sites

hah kym i have the same problem i think

well mine - the car kinda 'wanders' when i change lanes

think of it as high winds blowing the car and you can feel it slightly swerving in a way

sorry im not good at explaining

however, i wanna get rid of HICAS as problem is definately caused by it (HICAS warning light comes on regularly)

Link to comment
https://www.sau.com.au/forums/topic/15988-help-diff-problem/#findComment-331203
Share on other sites

Guest Boxhead

from what i know, if your doing one wheel burnouts, its a open diff, which either means thats what it is in your car, which is un likely, or your lsd is going bye bye, myn gives bad feedback, makes horrible clicking noises, and chooses when it wants to do 2 wheel burn outs, ive been told it is on its way out, and some say its the way it is.. ohwell.. if anyone knows were to source cheap GOOD diffs, sing out

Link to comment
https://www.sau.com.au/forums/topic/15988-help-diff-problem/#findComment-331225
Share on other sites

afaik the R33 GTST has a viscous LSD , not a mechanical as per a GTR.

Viscous relies on silicon gel to heat up caused by a different turning rate in the axles.

If the diff is a bit old , this may take time to react if it does at all.

The waving or lane changing is more related to w/alignment , tyre pressures , shot tyres or slack bushings.

What you have to realise is the hicas works in the same direction as the front wheels above 60kmh ( or so ) and only move by 1 or 2 deg anyway.

Cheers

Ken

Link to comment
https://www.sau.com.au/forums/topic/15988-help-diff-problem/#findComment-331232
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Structured text and other high level PLC programing languages are not allowable in Functional Safety. They are very difficult to audit. My PLC stuff is almost exclusively oriented towards Burner Management Systems which are a particularly pernicious form of Safety Instrumented System, when implemented in an SPLC. Even the part of the code written to work in the non-safety logic part of the PLC, like with a Siemens S7-1500 series, still needs to be treated as if it was safety code, with access restrictions, code fingreprints and the like. And Allen Bradley can go EABODs. They ae full of shit. They have this whole lie going on where they say if you use a ControlLogix controller and its IO, and then just duplicate the IOs (ie, run in series or parallel depending on type, to try to make it "fail safe") and "use these programming styles and place these restrictions on what you do" that you can achieve SIL2. What a load of crap. They just get away with it because no-one in the US seems to understand the first thing about Functional Safety and carries on as if all they have to do is buy only SIL2 rated equipment and hey presto, it's a SIL2 system. Idiots. /rant
    • If you're really considering leaving it, a great question to ask is, is the magnet going to stick to the sump? The answer to the above is the same answer towards if I'd have any level of comfort leaving it... Personally, based on the cost of a motor if the magnet were to cause damage, I'd be fishing it out either way. Use the methods in here. It fit in through the plug hole, it'll come out.   PS, get a small actuatable claw for a bore scope. OR if you know a vet, they have really cool controllable scopes with hooks on the end. Supposedly they're like playing a video game. Ask if they can acquire you one of their scopes... Engine oil after all is just a different type of lube right? Will only make it easier on the next dog or cat...
    • All other (Boolean) logic functions though, are just built on those blocks above. Which does give you a lot of functionality in logic. It is basing that on using thresholds with analogue signals like GTS alluded to.   Not having things like timers will make it less useful for some of the ramp up logic you'd want, and again, on Haltecs capacity specifically, I'm not across anymore what you can / can't do with different tables.   I'm assuming, with your logic you want to implement, not only do you want your timing safeties, you're wanting to be able to derive the duty cycle for your solenoid, to maintain I'm assuming 175PSi? Or are you using a standalone WMI controller to maintain the DC correct, and you just want the Haltech working out which fuelling maps you should be on?
    • It doesn't seem to follow revs. Oddly it seems to follow TPS a little bit from what I can see, but with some delay a bit. IE end of the graph, when he lets off throttle fully, pressure drops a lot, then slowly builds back up, but rpm is on a nice cruisey drop off. I do agree though, it seems very electrically.
    • I just try to entirely stay away from ladder now unless it's something basic maintained by electricians. Even then and to your point, it mostly ends up being blocks I wrote in structured text.  PLC's are slowly going towards C, C++ and C#. I just wish Allen-Bradley would jump on the bandwagon. 
×
×
  • Create New...