wackosr Posted May 11, 2011 Share Posted May 11, 2011 Afternoon folks. Just wondering if anyone can shed some light on a problem I've got? When shifting up quicky through the gears and giving her some beans, I get a spot of griding going into 5th unless I shift slowly and ease it in! What could be the cause of this, other then bad gear changing?! I'm hoping it's nothing major. Cheers Jacko Quote Link to comment Share on other sites More sharing options...
Husky Posted May 11, 2011 Share Posted May 11, 2011 the synchromesh in 5th is likely wearing. From now on take your time going into this gear, do not skip to it (eg 3rd to 5th). Get your gear box oil changed making sure high quality stuff is put in and maybe molislip (think thats the name) added. take care/time when the box is cold. The synchros are inside the gearbox and are not a readily servicable part, the gearbox can however be refurbished if it gets really bad and you can :pmr35lee: relating to this. I had the same issue as this in 5th which then went onto 6th gear as well, I required a new gearbox in the end but mine was a VERY bad example of this issue so don't panic. Quote Link to comment Share on other sites More sharing options...
Husky Posted May 11, 2011 Share Posted May 11, 2011 for information http://en.wikipedia.org/wiki/Manual_transmission Synchronized transmission Most modern cars are fitted with a synchronized gear box. Transmission gears are always in mesh and rotating, but gears on one shaft can freely rotate or be locked to the shaft. The locking mechanism for a gear consists of a collar (or dog collar) on the shaft which is able to slide sideways so that teeth (or dogs) on its inner surface bridge two circular rings with teeth on their outer circumference: one attached to the gear, one to the shaft. When the rings are bridged by the collar, that particular gear is rotationally locked to the shaft and determines the output speed of the transmission. The gearshift lever manipulates the collars using a set of linkages, so arranged so that one collar may be permitted to lock only one gear at any one time; when "shifting gears," the locking collar from one gear is disengaged before that of another engaged. One collar often serves for two gears; sliding in one direction selects one transmission speed, in the other direction selects another. In a synchromesh gearbox, to correctly match the speed of the gear to that of the shaft as the gear is engaged, the collar initially applies a force to a cone-shaped brass clutch (I believe this is what has worn in your box) attached to the gear, which brings the speeds to match prior to the collar locking into place. The collar is prevented from bridging the locking rings when the speeds are mismatched by synchro rings (also called blocker rings or baulk rings, with the latter being spelled balk in the U.S.). The synchro ring rotates slightly due to the frictional torque from the cone clutch. In this position, the dog clutch is prevented from engaging. The brass clutch ring gradually causes parts to spin at the same speed. When they do spin the same speed, there is no more torque from the cone clutch, and the dog clutch is allowed to fall in to engagement. In a modern gearbox, the action of all of these components is so smooth and fast it is hardly noticed. Quote Link to comment Share on other sites More sharing options...
wackosr Posted May 11, 2011 Author Share Posted May 11, 2011 Hi husky, Many thanks for the info, I'll get the oil and additive sorted out asap. Hopefully that and changing slowly will do the trick. I'll be sure to should it get worse with time. Sorry to hear that, did it set you back a lot if you don't mind me asking? Just something for me to bear in mind!! Cheers Quote Link to comment Share on other sites More sharing options...
wackosr Posted May 11, 2011 Author Share Posted May 11, 2011 Must learn to type faster, your second post appeared after I'd sent mine!! Very informative and interesting, thank you. Fingers crossed there isn't too much wear. Cheers Jacko Quote Link to comment Share on other sites More sharing options...
Husky Posted May 11, 2011 Share Posted May 11, 2011 Hi husky, Many thanks for the info, I'll get the oil and additive sorted out asap. Hopefully that and changing slowly will do the trick. I'll be sure to should it get worse with time. Sorry to hear that, did it set you back a lot if you don't mind me asking? Just something for me to bear in mind!! Cheers R35LEE sorted out for me at a good price but it still cost 4 figures after it took the clutch and flywheel with it too. (I'm not sure if alex offers a refurb service in scotland?). By the end it was completely unusable, when Falcon Performance took it out they said it was a lost cause and was completley full of swarf. it's a manufacturing issue from nissan as far as i'm aware as mine started dying after the car had done only 25k miles. Quote Link to comment Share on other sites More sharing options...
Husky Posted May 11, 2011 Share Posted May 11, 2011 Must learn to type faster, your second post appeared after I'd sent mine!! Very informative and interesting, thank you. Fingers crossed there isn't too much wear. Cheers Jacko no worries, hope it all goes well for you Quote Link to comment Share on other sites More sharing options...
wackosr Posted May 11, 2011 Author Share Posted May 11, 2011 Ouch, that's not good!! Mine has down 53K miles currently and I've not had it long so I've no idea how long it's been going on for! Best keep my fingers crossed!! Cheers Jacko Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted May 11, 2011 Share Posted May 11, 2011 1st step would be to swop out the old fluid with some genuine stuff and add 65ml of DC Moly, all of which I have in stock. Failing that if the box gets worse then a low mileage preowned box would be the most cost effective option, again boxes in stock, all with 12 months unlimited mileage warranty. 3rd option is an overhaul, which will give you a reconditioned transmission, this can be done on exchange basis or I can recondition your existing box. again 12 month warranty applies. Alex. Quote Link to comment Share on other sites More sharing options...
wackosr Posted May 12, 2011 Author Share Posted May 12, 2011 Hi Alex, Thanks for you help. Would you mind PMing me with part no's and prices for the following please? May as well get all the fluids changed. Gearbox Oil DC Moly Engine Oil Diff Oil Brake Fluid Also, could you give me an idea of price for the cheapest gearbox repair/refurb option please, just in case things go down hill. Thanks in advance. Jacko Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted May 12, 2011 Share Posted May 12, 2011 Hi Alex, Thanks for you help. Would you mind PMing me with part no's and prices for the following please? May as well get all the fluids changed. Gearbox Oil DC Moly Engine Oil Diff Oil Brake Fluid Also, could you give me an idea of price for the cheapest gearbox repair/refurb option please, just in case things go down hill. Thanks in advance. Jacko PM sent Jacko Quote Link to comment Share on other sites More sharing options...
wackosr Posted May 12, 2011 Author Share Posted May 12, 2011 Hi Alex. Have PMed you, thanks. (Must admit I sent it twice, wasn't in sent box initially, so thought I hadn't sent it, sorry) Jacko Quote Link to comment Share on other sites More sharing options...
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