LS1 Grinding into 6th

[johnno010684]

Hey guys, i have been having trouble with my vx clubby for a while, when changing into sixth it will feel like its slotted in but it will grind so i put clutch back in, and put it into sixth again and no worries. it only use to do it occasionally before now it does it nearly everytime!! has anyone had this problem or have any ideas?

[TonyJZX]

i think i've used 6th a handful of times to see if it actually exists

i think you have two choices

service the gearbox with a flush (transmax-z or penrite mgo 70 is good but expensive) and see if it gets better

i would assume you would have to pull the box out and open it up to really fix it ($$$)

or just live with it

[johnno010684]

yeah true, clubby diff ratio is different than ss m6's to make 6th more useable, i use it doing 80kmh sometimes. any ideas on how to do a gearbox flush/oil change over?

[bogan_vk]

it could possibly be the syncro gone in 6th gear if it grinds into that gear

[macca33]

Yep, using 6th at 80kph under load WILL result in you breaking something. 5th and 6th gears use some plastic components, believe it or not and if you place them under too much strain, being plastic, they break.

Try changing the fluid to Penrite MGO70 (Manual Gearbox Oil 70) and see how it comes up. You may simply have to live with it, or get it rebuilt - entirely up to you in the end.

6th gear is only good for 100kph+ - even in an HSV.

cheers

[db_notso]

plastic???
never noticed is it baker lite?
any way sounds like sixth gear synchro is binding up box out rear case off synchro
but if not enough experience with boxes get it rebuilt

soryy my memorys a little fuzzy on internals normaly we send them to get done
as we dont have the time to strip and assess internal damage

i think the sixth gear sits behind rear internal plate on these as an overdrive gear? i cant remeber exactly