Alpha Omega Racing Gearbox Rebuild

Discussion in 'Technical' started by Boll!, Mar 15, 2019.

  1. Boll!

    Boll! Well-Known Member

    Hi All.
    Has anyone used the team at Alpha Omega Racing for a gearbox rebuild?
    Their ad states they have a fix for the 4 gear crunch that some may experience.

    Interested to get some feedback.

    Cheers.
    Col
     
  2. ZXOCET

    ZXOCET Member

    Used them for a full manual rebuild with OS Giken close ratio gearset, heavy duty input shaft and sandwich plate as well as forged PPG selector forks. Very satisfied. Not cheap but quality work
     
  3. bobbs

    bobbs Member

    What do they do to fix the 4th gear crunch?
    Also I may be in the market for a new gearset... As even though I've rebuilt mine with all new parts, the actual gears are shagged. Noisy but still work. Though I think they're eating themselves due to the metal I'm seeing in the oil. Also really hard shifting into 1st though I suspect thats either caused by the Nismo trans mount (height is wrong) or the clutch needs more adjustment.
    Looking at Gikens website, they don't list the z32. I've read online that our gearbox is similar to R33 RB25 gearbox internals, but don't know if there is any truth to that.
     
  4. zx299

    zx299 Well-Known Member

    FS5W30A
     
  5. bobbs

    bobbs Member

    vs FS5R30A? Type-A?
    Single/Twin syncros?
    I suspect there must be a lot more to it...?
     
  6. Shane001

    Shane001 Well-Known Member

    What oil are you running? And what color metal?
    Start with an oil change to limit any further deterioration. The 'recommended' oil for our gearboxes (from memory) is Redline MT-90, though I'm running Redline LightWeight Shockproof in the race car.
    LWS might be better since yours is already deteriorated.
     
  7. bobbs

    bobbs Member

    After the rebuild, I don't know what brand or viscosity. It was just recommended and supplied by them. I suspect it was a poor quality mineral oil as the second batch I was about to refill had some kind of clumping of slimy growth. I've since refilled it with Penrite full synthetic 75W90. That fixed the gear noise on 4th gear for about 100km... but the grinding noise has since returned. The metal were fine needles of steel as they were stuck to magnetic plug. I assume its from 4th gear teeth as there is no bearing like noise in 1st, 3rd or 5th. Second gear has always been noisy (2nd wines like straight cut gears, 4th sounds like gear teeth grinding itself to dust).
    Unfortunately the gearbox rebuild is way out of warranty as I hardly ever get to drive her :( plus there probably wasn't any warranty on the old gears anyway
     
  8. Shane001

    Shane001 Well-Known Member

    Get that Penrite shit out of there asap.

    I ran a Penrite oil recommended for the gearbox in a Mitsubishi FTO (previous racecar). First session on track didn't feel right. Drained the oil. Full of tiny little golden flecks of metal! Switched to a Motul oil for the FTO and never had an issue.

    Put Redline LWS in it.
     
  9. rob260

    rob260 Administrator Staff Member

    Are you running the GL4 or GL5 Penrite oil?

     
  10. bobbs

    bobbs Member

    It's GL5. I have only done about 300kms on that oil.
    I have read that it can cause tarnishing on brass components, such as syncros. But I've also read that it's fine. The shop didn't have GL4 in 75W90 only GL5. Still making gear noise though, which I don't think would matter if it was GL4 or 5.
    If I can finish putting my wifes car back together (wheel bearings), I will drop the oil and buy from somewhere else.
    Where can I find Redline LWS in western sydney? Full synthetic? Weight/viscosity?
     
  11. rob260

    rob260 Administrator Staff Member

    Well there’s at least part of your problem.

    GL5 is too slippery.

    I would be pissed off if I had paid a Workshop to knowingly put the wrong oil in.

    Redline lightweight shockproof is also a GL5. Ie wrong. @Shane001 kmows this is just stubborn -reminds me of someone I know lol.

    If you are going to put redline in you should use MT90. Or get the GL4 penrite.

    This may not solve all or even some of your problems but I dare say putting the right fluids in is a good place to start.
     
  12. bobbs

    bobbs Member

    I think it just needs new gears. Sure, I could probably put in some ATF to try to mask the problem, but at the end of the day, I suspect the gearbox I bought of a member here was run without any oil. My reason to believe so was - the oil fill plug was glued in so hard the case had to be split, drilled out, smashed a cold chisel in the hole, lots of heat from an oxy acetylene torch and the full body weight of 2 fat people to get it out lol.
    I suspect that once a gear face has been damaged, any further running even with good oil and only light load, the gear profile is ruined and thus will eat itself. I think maybe one of the telltale signs is there seems to be a lot of backlash in the gears. e.g. noticeable at slow speed coasting when transitioning between accel/decel. Transition has to be smooth otherwise the sound of gears clacking wont be pleasant.
     
  13. Shane001

    Shane001 Well-Known Member

    Not stubborn at all mate, works perfectly well and have had zero problems with my gearbox being thrashed on the racetrack for the last 5 years including a few embarrassing crunched gear changes and running flat out to redline at every gear change for an hour at a time.
    If you ask Redline directly they're not going to tell you to use it because it's not the 'correct' oil, but it's perfectly fine in our gearboxes and diffs, and for a gearbox that's already showing signs of bad internal wear it's probably the better option as it'll help mask some of that wear.
     
  14. Boll!

    Boll! Well-Known Member

    That sounds nice, was that in a Z32 box?
     
  15. zx299

    zx299 Well-Known Member

    I know your gearbox appears to have some problems (metal in oil), but noisy 2nd and 4th ??

    Are you sure your gear stick rubber boot hasn't come adrift ?
     
  16. bobbs

    bobbs Member

    Zx299. It has all new rubbers inside and out. I didn't notice anything unusual when I changed the oil last week. I may need to insert my mini flexible inspection camera through the drain/fill plugs to get a better look. However, it will probably just confirm my suspicions and will need to find a new gear set. I honestly have no idea where I will find them.
    Zxocet: can you give any more details on the parts used? I'm assuming its a z32 TT gearbox.
    Shane001: I was contacted by redline last night. Unfortunately there are no distributors in Sydney but they can ship from Perth. However he recommended against LWS as its for non syncro dog boxes. MT-90 would be the correct oil. Its also a GL4. So I cant see what would make it special compared to any other brand of oil with the same specs. I have never had a problem with Penrite brand with my engine oil. I'm not really interested in unscientific brand wars e.g. I've had friends swear that caltex fuel made their car faster than when they used shell fuel or that it ran 'crap'. Sorry but it sounds like a snake oil salesmans pitch.
     
  17. zx299

    zx299 Well-Known Member

    The 2nd and 4th gear being noisy due to the gearstick rubber boot is a known problem on manual zeds.

    The rubber boot starts to come off the lip on the transmission tunnel and lifts at the front when 2nd & 4th are selected (the lever throw must be longer for 2nd & 4th) allowing gearbox noise to enter the cabin.This gives the impression that 2nd & 4th gears are much noisier than any other gear. When 1st/3rd/5th are selected, the rubber boot is not lifted (presumably due to a shorter lever throw) and no gearbox noise enters the cabin

    This may not be your problem, but it's worth a couple of minutes to check out
     
  18. bobbs

    bobbs Member

    Next time I jack it up, I'll put it in gear and see if its lifting or split. It's brand new, so I doubt its split.
    If it was on the top side, I wouldn't have noticed anyway.
    Mind you, the sound of 2nd and 4th is completely different... But I'll double check anyway.
     
  19. Shane001

    Shane001 Well-Known Member

    Totally agree. I've simply offered my direct experience on the race track. Take it or leave it, doesn't worry me ;)
     
  20. IB

    IB ?????

    You need to take the shifter boot (and centre console/trim) off to check.
     

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