Z 5 speed jumping out of 5th.

[Dat Lurka]

Hey guys. My new 620 has a 5 speed from a Z and it's pretty freakin rough. It's very hard to shift and makes plenty of noise. I believe it's dry as a bone and I'm about to go outside and fill her up.

Could being dry cause it to kick out of 5th when accelerating?

If not, is it most likely a loose mainshaft nut? It is damn near impossible to shift into 1st or reverse. Or would it be bent shift fork? 

Should I drop it and tighten the mainshaft nut rather than filling it up?

[Dat Lurka]

Looking for answers.

Alternative is swapping 5 speed from other truck.

[bananahamuck]

http://www.zcar.com/forum/10-70-83-tech-discussion-forum/13450-5-speed-jumps-out-5th-gear.html

[Dat Lurka]

Thanks bananahannamananafanamana

 

I'm gonna fill it with grease and add a bungee cord.....

[bananahamuck]

yeah i think that`s pretty much your only fix without disassembling and replacing a bunch of probably really overpriced parts.... from what i have read i think 2nd gear will follow eventually ....but i don't know why.

[72240z]

A 280zx (fs5w) bearing and seal rebuild kit is like 40 bucks. I was rebuilding cores to flip at one point. 

Knowing how to rebuild the trans is the issue here I bet lol. Just buy another used one would be my advice or bungee it I guess. 

[Dat Lurka]

Keep in mind I'm in nowheresville East Coast. 

The 5 speed in the other KC works great. Make one great truck out of two. Got a good 4 speed to put in.

[72240z]

I'm sure you can get a zx 5 speed at a junk yard, craigs or in the z forums or shit even ebay. Was selling and shipping mine on there just fine. 

[metalmonkey47]

Keep in mind I'm in nowheresville East Coast. 

The 5 speed in the other KC works great. Make one great truck out of two. Got a good 4 speed to put in.

 

 

Toss in your 4 speed, bring the 5 speed to ATL, and pay Master-o-turbonics to rebuild it. He's done a couple so far. 

[metalmonkey47]

A 280zx (fs5w) bearing and seal rebuild kit is like 40 bucks. I was rebuilding cores to flip at one point. 

 

Knowing how to rebuild the trans is the issue here I bet lol. Just buy another used one would be my advice or bungee it I guess. 

 

Where are you finding the rebuild kits for $40? 

[Dat Lurka]

Junkyards around here have scrapped just about everything before 1998 

I'm gonna fill it up and see if it fixes the grinding and noise. I can live without 5th gear.

[72240z]

Where are you finding the rebuild kits for $40? 

 

Cobra transmission still stocks them I believe. Last I checked pre shipping it was like 35 bucks for a bearing/seal kit and 130 for a complete kit with syncros. 

[datzenmike]

All you need is a crescent wrench to tighten the mainshaft nut. Should be 100-120 ft lbs. ... so if loose or has backed off, this is your problem. The mainshaft nut backing off was a problem with the early 5 speeds and yours qualifies.

 

Don't use grease or on cold mornings you won't be able to get it out of gear.

[Dat Lurka]

Thanks Mike I'm gonna drop it tomorrow evening and take a look. Worth a shot before I fill it up with fresh oil.

[datzenmike]

Obvious nut is obvious...

Yours will likely have the speedo worm gear to the back but you get the idea.

[Dat Lurka]

thanks

Also, the speedo is 10mph off. 40 is 50 etc. Is there a way to fix this? I didn't check but I think the tires are right. Figured it was because of the Z trans.

[72240z]

the speedo cog int he trans prob doesnt match the rear end in the truck. Idk which cog you can use, Mike prob knows. You can order them still I think. 

This is from NZdatsuns
3.3?? : Yellow
3.545 : Black
3.7 : Blue
3.9 : White
The following rear gear ratios were only available from Nissan Competition Dept. - not OE in any models sold in the US
4.11 : Red
4.375 : Purple?

[Dat Lurka]

I've never seen a rear end like the one I have. But then again I've never had a 78. It's finned on the front and has the funky semi circle bracket thingies on the bottom.

[72240z]

Well worse case you can put the ass in the air and count rotations to find out the ratio then get the coinciding cog or closest you can find. 

[Dat Lurka]

Alright I'm having trouble dropping the transmission. Either the front lands on the clutch or the tail hits the floorboard. What am I missing here?

[72240z]

Why cant you tilt the motor? 

[datzenmike]

Take the driver's torsion bar out and roll it to the left?

[wayno]

Did you remove the tunnel cover, does the 620 have a tunnel cover?

If you have to, you can slide the transmission back as far as you can get it, then remove the clutch cover, then remove the tranny, but remember to put the tranny back up in there before you put the clutch cover back on.

You are lucky, I used to have to remove the flywheel also to get it out.

[Dat Lurka]

Taking a break by the fire to thaw my frozen back.

 

I think I can get it out by removing the clutch cover. I can roll it towards driver side and clear the torsion bars. It's the starter hump that catches. I'm trying to avoid removing the torsion bar. Sounds like a bigger pita. 

Thanks guys.

 

If only that one part of the frame was 4 inches farther back...

[Dat Lurka]

Got nice and toasty then went out for round 4. Jacked up the tail and got under the front of the truck and kicked the motherfucker over the tortion bars. Jacked up the motor by the pulley, flipped the trans towards the driverside best I could and pushed it against the exhaust with both legs. Dropped it like its hot. Slung the bitch out from under the truck and stuck it in my dump bucket.