Jump to content
SAU Community

Recommended Posts

Good notes Adam!

Definitely one of the biggest themes of the day was how the driveline is designed with shock absorbing capability, and changing this with stiffer components can lead to damage if the whole system isn't appropriately matched.

Yeah i reckon its something like this below - area under the curve is the same, but peak load/force is much lower with a soft (sprung) clutch. Engineering 101.

114937-largest_asphalt_545.jpg

  • Like 1

Cheers guys for another great tech arvo.

Thanks to Award, Terry and Trish :)

Learnt some new things and got in some laughs as well.

Thanks Adam for the notes as well!
Will be looking forward to the next one :)

Was a damn shame I missed this, with both sleeping in and my calendar reminder not set properly I got the reminder 10 min's before the event :(

"Solid mounting of diff cradles also increases rigidity in a way that's detrimental (for the gearbox? or drive train more generally?), so make especially sure you use a sprung center clutch if you have a solidly mounted diff cradle."

This is good to know as I've just fitted a diff craddle and will be putting in the g'box brace in soon too, guess with the brass button clutch this is going to destroy my gearbox prematurely. :) JOY hahaa

oh, and lol.. not sure how many people found out in the day, but it turns out Terry and Trish live 2 doors down from me. It didn't click until we went outside for the ridiculously big spread they put on and i saw their car.

all in all, i think i learnt more from this tech session than any of the others.... thanks to all involved in organizing and putting the day on.

shift sedately and you will be fine, so no time attack shifts for you just yet!

I'm sure you'll find it's not so much how you shift the box as it is how you reengage the clutch that destroys boxes, this will apply to both going up AND down gears, should be done just like a motorbike, find friction point then release clutch not find floor then release clutch

  • Like 1

The other bit I got out of the day (more informative than anything) is that the only major difference between the series 3 BCNR33 boxes and other 32/33 boxes is that the syncros are "pad-type" rather than held in by circlips and also have a stronger (bigger) 5th gear synchro making them the design of choice if you have the option.

He also recommended that cleaning the gearbox can be done by running ATF in it for a while. Could be useful for those wanting to move away from smurfsblood which is nearly impossible to remove.

It was also interesting that Terry mentioned there is not a major difference in the various LSDs out there however for big power/time attack cars he did seem to recommend the Cusco up front. Seems he can also modify the standard ones making it potentially a cheaper option.

I'm sure you'll find it's not so much how you shift the box as it is how you reengage the clutch that destroys boxes, this will apply to both going up AND down gears, should be done just like a motorbike, find friction point then release clutch not find floor then release clutch

brass button clutch what friction point ?? HAHA

It was also interesting that Terry mentioned there is not a major difference in the various LSDs out there however for big power/time attack cars he did seem to recommend the Cusco up front. Seems he can also modify the standard ones making it potentially a cheaper option.

Yeah i think we was saying that like gearboxes, which are pretty much all the same in how they work, the factory, Nismo, Cusco etc LSDs are also pretty much the same. He can setup the rear to be tighter, however, since the after market ones are larger/beefier they will last longer.

I destroyed 5 brass buttons in 2 years due to the torque and everyone of them had a friction point

The distance between off and on was very very small though

no worries I have no torque HAHA




  • Similar Content

  • Latest Posts

    • Surely somebody has one in VIC. Have you asked at any shops?  Is this the yearly inspection or did you get a canary?
    • This is where I share pain with you, @Duncan. The move to change so many cooling system pieces to plastic is a killer! Plastic end tanks and a few plastic hose flanges on my car's fail after so little time.  Curious about the need for a bigger rad, is that just for long sessions in the summer or because the car generally needs more cooling?
    • So, that is it! It is a pretty expensive process with the ATF costing 50-100 per 5 litres, and a mechanic will probably charge plenty because they don't want to do it. Still, considering how dirty my fluid was at 120,000klm I think it would be worth doing more like every 80,000 to keep the trans happy, they are very expensive to replace. The job is not that hard if you have the specialist tools so you can save a bit of money and do it yourself!
    • OK, onto filling. So I don't really have any pics, but will describe the process as best I can. The USDM workshop manual also covers it from TM-285 onwards. First, make sure the drain plug (17mm) is snug. Not too tight yet because it is coming off again. Note it does have a copper washer that you could replace or anneal (heat up with a blow torch) to seal nicely. Remove the fill plug, which has an inhex (I think it was 6mm but didn't check). Then, screw in the fill fitting, making sure it has a suitable o-ring (mine came without but I think it is meant to be supplied). It is important that you only screw it in hand tight. I didn't get a good pic of it, but the fill plug leads to a tube about 70mm long inside the transmission. This sets the factory level for fluid in the trans (above the join line for the pan!) and will take about 3l to fill. You then need to connect your fluid pump to the fitting via a hose, and pump in whatever amount of fluid you removed (maybe 3 litres, in my case 7 litres). If you put in more than 3l, it will spill out when you remove the fitting, so do quickly and with a drain pan underneath. Once you have pumped in the required amount of clean ATF, you start the engine and run it for 3 minutes to let the fluid circulate. Don't run it longer and if possible check the fluid temp is under 40oC (Ecutek shows Auto Trans Fluid temp now, or you could use an infrared temp gun on the bottom of the pan). The manual stresses the bit about fluid temperature because it expands when hot an might result in an underfil. So from here, the factory manual says to do the "spill and fill" again, and I did. That is, put an oil pan under the drain plug and undo it with a 17mm spanner, then watch your expensive fluid fall back out again, you should get about 3 litres.  Then, put the drain plug back in, pump 3 litres back in through the fill plug with the fitting and pump, disconnect the fill fitting and replace the fill plug, start the car and run for another 3 minutes (making sure the temp is still under 40oC). The manual then asks for a 3rd "spill and fill" just like above. I also did that and so had put 13l in by now.  This time they want you to keep the engine running and run the transmission through R and D (I hope the wheels are still off the ground!) for a while, and allow the trans temp to get to 40oC, then engine off. Finally, back under the car and undo the fill plug to let the overfill drain out; it will stop running when fluid is at the top of the levelling tube. According to the factory, that is job done! Post that, I reconnected the fill fitting and pumped in an extra 0.5l. AMS says 1.5l overfill is safe, but I started with less to see how it goes, I will add another 1.0 litres later if I'm still not happy with the hot shifts.
    • OK, so regardless of whether you did Step 1 - Spill Step 2 - Trans pan removal Step 3 - TCM removal we are on to the clean and refill. First, have a good look at the oil pan. While you might see dirty oil and some carbony build up (I did), what you don't want to see is any metal particles on the magnets, or sparkles in the oil (thankfully not). Give it all a good clean, particularly the magnets, and put the new gasket on if you have one (or, just cross your fingers) Replacement of the Valve body (if you removed it) is the "reverse of assembly". Thread the electrical socket back up through the trans case, hold the valve body up and put in the bolts you removed, with the correct lengths in the correct locations Torque for the bolts in 8Nm only so I hope you have that torque wrench handy (it feels really loose). Plug the output speed sensor back in and clip the wiring into the 2 clips, replace the spring clip on the TCM socket and plug it back into the car loom. For the pan, the workshop manual states the following order: Again, the torque is 8Nm only.
×
×
  • Create New...