Nissan 5spd, getting hard to shift into 2nd, couple Q's

[Guest bastaad525]

Hey all... just wanted a second oppinion on this. My nissan 5 spd may be wearing out a bit, or maybe this is just a sign that the oil needs to be changed I dunno.

 

Anyways, it's getting harder to shift the thing into 2nd gear. So I'm guessing of course, bad synchros, but the odd thing is, I've had synchros go bad on Z trannies before, and the result was always that it would start to grind a bit when trying to shift into gear, particular when trying to downshift. However, if I rev matched and/or double clutched, it would usually go in easier, grind less or not at all. However as time went on it would get worse and worse.

 

This time though, it's a bit different. For one, there is NO grinding when I try to shift, it's just harder to push into gear, it almost feels like something is blocking it from going in, and lately I really need to yank it in there sometimes. Also, rev matching and double clutching don't seem to help the situation at all or only very little.

 

The problem is worse when the tranny is cold.

 

Anyways... i think it's only been about a year and about 6000 miles since the last time I changed the trans oil, though it was kinda dark last time I checked it. Do you guys think the symptoms mean bad gears or just old oil?

 

Also, I have heard people mention that sometimes switching to a high quality or synthetic gear oil, like Red Line Shockproof gear oil, can make slightly worn trannies shift like new again... anyone here have some testimonials about Red Line or another like Royal Purple or any of those? Should I pony up the $50-60 to run one of these or it wont help?

[GrayZee]

Maybe it just needs a new clutch? If you do the clutch, make sure you machine the flywheel. Even simplier yet, check the clutch fluid and have somebody press the clutch while you watch the slave cylinder travel. If the slave dosn't move very much try pumping it and then see what happens.

[Guest bastaad525]

Nope, just replaced the clutch a few months ago... only have maybe 6000 miles on it... that's also when I changed the gear lube oil. The pedal travel is adjusted perfectly, it is fully disengaging at about 3/4 of the way down (you can hear the input shaft stop spinning). I also just replaced my master and slave cylinders about two months ago and bled the system at that point. Again this is only happening with second gear, and it's happening when upshifting or downshifting, so it's gotta be something with that gear.

[JMortensen]

Your mainshaft nut is coming loose I think. My transmission has never grinded gears, but I'm going to rebuild it because it has the mainshaft nut coming loose. I hadn't really associated the hard shifting with this problem because I only encountered that a couple times, but I did have trouble hitting second at an autox when I was trying to shift really fast. My main symptom is a bearing growl at idle with the clutch out, and more recently it pops out of gear while decelerating.

 

Any of that sound familiar?

[datsunlover]

I'm having a similar issue with my pickup (93 nissan 4x4) with 2nd and 3rd. I have 275 000 on her though, and I'm just assuming it's worn and there is slop..evrywhere. And yes it's worse in the cold weather. Sometmes I can barely get it into gear. The stock 4 gear in my 280 was the same; The faster you tried to shift, the harder it go to get into gear. My thinking is after a lot of use, the little 'tabs' that the shift rods work on get sloppy and out of alignment a bit..

[Guest bastaad525]

so we're agreed it's probably not synchros then. And it also sounds like nothing short of a rebuild will solve the problem I haven't noticed any bearing grinding noise.

 

 

So... is it worth going with a better lube like redline? I know some people do say that using these high $ gear oils helps smooth out problems like these.

[JMortensen]

If it isn't a synchro problem lube won't fix it.

[Z-Gad]

You may want to check the shifter bushing on the bottom of the shifter. If it is broken or now missing altogether, it could create enough slop that the gear could be harder to find. You probably have a rebuild in your future though

[datsunlover]

If you're gona pull it to rebuild, I'd say just swap in another.. depending how availible 5 gears are around you, you'll probly be able to find a used one for well.. cheaper than rebuilding the current one. There's the KA 5 speed (240sx) swap too.. I've got mine together for under $200 now, but there is a bit of 'fiddleing' to make it work... Just a thought..

[srgunz]

I have a 72 with a 5 speed also. Anyway this exactly has happened to me a few times over the years. What always worked for me is to put fresh fluid in the master and slave. I have always done it myself just gravity bleeding it at the slave cyl. All the clutch disc has to do is just barely drag when released and it will show up on 2nd gear first. The others will work fine.

The last time I bled, I also discovered the clutch pedal pin was worn. Put in a new one and is just like butter now.

I learned this from the MG's and Triumphs I owned. Same exact problem.

Anyhow try this first before doing anything drastic.

[Guest bastaad525]

Yep I just put fresh fluid in not long ago, when my master cylinder went bad, and drained all over my floor Anyways replaced the master and slave and put fresh fluid and bled it pretty thoroughly.

 

I do have my clutch pedal adjusted to engage pretty low though, and there is some slop there from a worn pedal pin and the bracket that attaches the pedal to the master cylinder rod. I had to reuse my worn out bracket since I have modified it slightly to give me more adjustment with the heavy aftermarket pressure plate I run (welded a nut on the back of it, basically extending it about 1/3"). I have plenty of adjustment space left with that mod, so I will adjust it up a bit to engage higher in the pedal travel, and see if that helps. I'll also re-bleed the clutch, just in case.

 

Now that you mention it, this does kinda make sense because I did kinda feel like, after changing cylinders, that I maybe adjusted the pedal to take up a little TOO low, slightly lower than I'd had it before, and I really had to make it point to push the pedal ALL the way down like if I'm trying to shift fast or whatever, or sometimes if I haven't driven the car in a while I might stall or jerk a bit when leaving a stop... so yeah it's probably adjusted a bit TOO low I HOPE that's what it is....

[Pop N Wood]

I hope that is it also. My Tacoma is doing the same thing on first and second gear. At 20 degrees I simply can't push it hard enough to get in 2nd gear without double clutching. Only have 80K miles on the truck. I tried switching to Mobil 1 gear oil and that seemed to help, but haven't seen the really cold temps to know for sure.

 

My clutch pedal has squeaked for the last two years. Something to look at.

[Guest bastaad525]

I adjusted the pedal-to-master cylinder rod just a tad, about 1/4 turn out, and yeah it does seem to have helped. I really did have it adjusted low... I was listening very close and you could hear the clutch start rubbing on the flywheel faintly, after letting the clutch pedal out even the slightest bit from completely bottomed. I may adjust it just a tad bit more... little adjustments seem to make a lot of difference. Anyways drove the car to work and tried a few downshifts and I didn't have to YANK it when downshifting into second.

 

 

I think part of it is also that I'm just so used to the Sentra now, which has a much more rubbery, smooth feeling shift... I'm so unused to the Z's much more mechanical, metal on metal feeling shift that I think it kinda exaggerated the problem in my mind... the whole thing just felt much better today. So... *phew* guess this means I may be in the clear! I think I'm still gonna make a point of changing the gear oil soon and switching up to a better oil like Mobil 1 synthetic or Red Line shockproof. I'll post here if that makes any difference.