kerristallax Posted May 27, 2013 Share Posted May 27, 2013 Got my s1 Rb25 280z on the road finally Saturday. Still have some wiring to clean up and other odds and ends. What transmission fluid are you guys running in the RB 5spds? I put ~4 qts of Redline MT90 in this one, it seems mostly OK except for the occasional notchy / clunky shift into 2nd. A google search turned up that Redline MT90 is pretty commonly used in the RB manual transmissions. I know that was what my old z31 and the 280z transmission liked also. Is the occasional notchy shift into 2nd just something that these boxes do? Quote Link to comment Share on other sites More sharing options...
ZT-R Posted May 28, 2013 Share Posted May 28, 2013 I use MT-90, no issues, except massive Carbonetic twin disk clutch slippage... Quote Link to comment Share on other sites More sharing options...
kerristallax Posted May 28, 2013 Author Share Posted May 28, 2013 I'm running the dxd (south bend clutch) stage 2 clutch and pressure plate on the stock flywheel. Clutch seems to engage as soon as I start releasing the pedal. That's different than how the stock clutch on my old l28 setup was, which is the only thing I have to compare it to. Quote Link to comment Share on other sites More sharing options...
wrcbonk Posted May 29, 2013 Share Posted May 29, 2013 I had the same notchy shift into 2nd as well. I put in a couple quarts of redline mt90 and a quart of gm synchromesh and that seemed to fix the notched shift. Quote Link to comment Share on other sites More sharing options...
flatrate Posted June 1, 2013 Share Posted June 1, 2013 Torco RTF works well, trans is a bit noisy with the lighter fluid.. i also like redline Lightweight shockproof Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted June 1, 2013 Share Posted June 1, 2013 Redline Lightweight Shockproof for mine also... Quote Link to comment Share on other sites More sharing options...
kerristallax Posted June 3, 2013 Author Share Posted June 3, 2013 Are you running the lightweight shockproof straight, or mixed with mt 90 / another fluid? I had to fill my transmission through the shifter because the fill plug was fused in there something fierce. Put in 3.8 quarts of mt90. That should have been enough based on what I was able to find...? I'm trying to locate the correct square plug socket to properly remove the fill plug and check the level. I think ktc tools makes one, 13mm male square plug? A 1/2 drive ratchet was a little too small in the fill plug and slipped some, naturally dorking it up in the process... Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted June 3, 2013 Share Posted June 3, 2013 Are you running the lightweight shockproof straight, or mixed with mt 90 / another fluid? Strait is how mine is. I'm not implying this is a better trans oil, it's just what I tried using and have had no complaints using it so far.... Quote Link to comment Share on other sites More sharing options...
///M3 & Z Posted June 4, 2013 Share Posted June 4, 2013 I used the z32 trans in my setup with 3 litres of liqui moly 75 w90 Quote Link to comment Share on other sites More sharing options...
johnc Posted June 4, 2013 Share Posted June 4, 2013 FYI... Shockproof is primarily designed for dog ring racing transmissions with straight cut gears (Hewland, Quaife, Jerico, etc.). Its way overkill for for any normal OEM transmission and might cause problems down the road due to its affinity for metal particles - the particles stay in suspension and continuously move through the transmission. That's not an issue for a racing trans that gets the fluid changed a dozen times a year. Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted June 4, 2013 Share Posted June 4, 2013 FYI... Shockproof is primarily designed for dog ring racing transmissions with straight cut gears (Hewland, Quaife, Jerico, etc.). Its way overkill for for any normal OEM transmission and might cause problems down the road due to its affinity for metal particles - the particles stay in suspension and continuously move through the transmission. That's not an issue for a racing trans that gets the fluid changed a dozen times a year. Thanks for that info john. I will put it to use asap. Now, to learn which lube would be ideal to use in this street driven trans. Quote Link to comment Share on other sites More sharing options...
TimZ Posted June 4, 2013 Share Posted June 4, 2013 (edited) FYI... Shockproof is primarily designed for dog ring racing transmissions with straight cut gears (Hewland, Quaife, Jerico, etc.). Its way overkill for for any normal OEM transmission and might cause problems down the road due to its affinity for metal particles - the particles stay in suspension and continuously move through the transmission. That's not an issue for a racing trans that gets the fluid changed a dozen times a year. Ah HA! That's why they recommend "For Racing Use Only" for those oils - I've never heard a straight answer on that until just now! Edited June 4, 2013 by TimZ Quote Link to comment Share on other sites More sharing options...
johnc Posted June 5, 2013 Share Posted June 5, 2013 Shockproof is formulated with small lubricating particles in suspension to help dissipate shock loads (gear to gear and dog to dog). Because its formulated to hold the particles in suspension it also holds metal particles. Regular gear oil is formulated to not hold particles in suspension6 and allow them to drop out to the bottom of the case. Quote Link to comment Share on other sites More sharing options...
ZT-R Posted June 5, 2013 Share Posted June 5, 2013 MT-90 Quote Link to comment Share on other sites More sharing options...
kerristallax Posted June 5, 2013 Author Share Posted June 5, 2013 Mt-90 has always been my go-to fluid for Nissan transmissions. That does kind of explain why the lightweight shockproof helps worn synchros if you think about it. On another note, I increased the length of my clutch master cylinder pushrod last night and took it for a test drive. The shift from 1st to 2nd was better than it had been previously. 2nd to 3rd was still so-so. Not terrible, but not exactly smooth either. Will get another drive on it and report back. Is there a such thing as having the clutch pedal pushrod adjusted too long? The clutch engages now in the top 1/3 range of the pedal, instead of at the very bottom. I did adjust the stop too so it still has the right amount of free play in the pedal. Quote Link to comment Share on other sites More sharing options...
kerristallax Posted June 7, 2013 Author Share Posted June 7, 2013 Update - scratch that last post, it was just a case of shifting fast enough before the revs dropped. Like many others that seem to have the same problem, it is fine for fast or slow shifts, it only is notchy on "normal" shifts. Borrowed the 13mm square plug socket and will try to properly check the fluid level this weekend. Quote Link to comment Share on other sites More sharing options...
kerristallax Posted June 17, 2013 Author Share Posted June 17, 2013 I tried swapping out the transmission fluid for Amsoil MTG over the weekend, which is another gl-4 75w-90. For only 200 miles on the mt-90 it was sure dirty when I drained it. A deep black/brown color. I didn't get any bits and pieces on the drain plug magnet, which was a small relief. Initial impressions of the Amsoil are an improvement from where it was. Quote Link to comment Share on other sites More sharing options...
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