Redline Shockproof in the gearbox.....

[kaptainballistik]

Hi all. Need some opinions. For a rallycar...

Im sticking Redline Shockproof Heavy into the VR4's transfer case, And was going to Put it into the gearbox as well. ( well, it works in Subi's...)

Is it better to run shockproof light or heavy in the gearbox ( Its old....it had sparkly's in the oil too... /ubbthreads/images/graemlins/frown.gif )

And 5th is crunchy and reverse doesnt like staying in.... Its not a Rotary, I dont know /ubbthreads/images/graemlins/dunno.gif

 

[ktmrider]

There's a bunch of info floating around regarding this.
Short story, the gearbox runs GL-4 rated lubricant. Prove_it was asking about ZDDP additives and I posted up a bunch of links on the subject. You might get smoother shifting initially but there is potential for long-term damage to the brass syncros and bushings ( possible reason for your sparklies ).
Oh and Shockproof is GL-5 rated so you be the judge.

 

[kaptainballistik]

Im currently running Penrite mineral based( I do in the Rx2 with no issues...) So I havent put in the Redline yet.

Long term bushing life is not my main concern, Its getting the gearbox to keep 3rd gear in one piece! Ill happily sacrifice Syncro life for a gearbox that doesnt self destruct................

 

[ktmrider]

So long as you make an educated decision! /ubbthreads/images/graemlins/wink.gif

 

[CP]

Shockproof kills the synchros. Skip. Good in the trans case and rear diff.

 

[kaptainballistik]

Hmm, The box is a bit worn so a rebuild is due ( Was for this rally but Moving sorta threw a spanner at that.......)

More info the merrier!

Which also brings the question, Will it work in a Cusco 1.5 rear diff?

 

[turbowop]

I suggest NEO RHD. Expensive, but good protection for gears. I've been using it for a few years now.

 

[Street Surgeon]

When I had my trans built I sent shep an email asking the same thing, this was his reply.

Shep:
"There is no perfect gear oil for everyone. On the higher horsepower cars we have been leaning towards using either straight lightweight shockproof or mixing one of the thinner fluids like the bg etc with some redline heavy shockproof.
Thanks
John Shepherd"

ME:
"What would you recommed for my transmission around 400hp?"

Shep:
"mix a whole bunch together and throw it in /ubbthreads/images/graemlins/smile.gif Seriously try running lightweight only. If you have issues shifting then try thinning it out.

Thanks
John Shepherd"

 

[Lonewolf64]

John over at TRE recommends against using any gear oils with paraffin additives like Redline Heavy/Light Shockproof. Due to the centrifugal forces at work in the transmission, the paraffin comes out of the oil and blocks important lubricating passages, leading to shot synchros and more problems. He also recommends against Synchromesh because it is too thin to properly protect the transmission from damage.

John recommends Redline MTL or Redline 75-90 gear oil in all our transmissions.

 

[skivittlerjimb]

Has anyone used Motul Gear 300 75w90? A local friend/shop owner just became a Motul distributor and I'm thinking of trying it out.

FWIW, I don't think I'd ever put 100% Heavyweight Shockproof in the tranny. I'm thinking of going that route this summer for the t-case and rear-diff, though.

-Jim B.
280/1000

 

[Dan D]

I've run Syncromesh for the last 80k miles on a 192k mile transmission. 300whp'ish car. Still shifts fine.

I think the choice of fluid and the results have more to do with driver habits than anything else. If you tend to smash the sh*t out of your gears, you better have something with good protection. If you rev really high you needs something that will not breakdown and separate. For a modestly driven car without a lot of horsepower (like mine) you can probably put Valvoline gear oil in it and be fine.

 

[kaptainballistik]

Well, The oil worked..... Pity the driver tagged a bank! ( Got it fixed and did the last 7 stages , Damm these things are tough) Standard arms really do stop you bending the crossmember!

Anyway, The Redline heavy worked a treat, Reverse will not select anymore ( It was going...the cable was bowing when you tried to select it..)

but 5th has barely a snick when you changed, And the transfer case didnt loose a drop.