redzedturbo Posted September 20, 2016 Share Posted September 20, 2016 Hey guys i have a drive shaft vibe i can not get to go away. But to be fair im running an odd setup that few if any are running. I have a rs5r30a z32 trans in my turbo zx. Im using a hoke adapter and a 3.6" diameter aluminum driveshaft with 1310 to 1350 u joints. the slip yoke is a pathfinder spicer unit and the diff flange is from jagsthatrun. Anyways i have been running this all year with very limited but there vibration. After installing some poly bushings in the sub frame and rear control arms i used a angle gauge to check my drive shaft angle today at work. (over a pit with car on ground) the trans is pointed down 2.5 deg and the diff 5 deg up. The driveshaft at the center is 2 deg's up to the trans. so i thought hey ill drop the trans to get the same 5 deg's down as the diff is up right? after i did this the whole way home i had floor knocking vibrations when i took off and under any throttle squeezing at all. I dont claim to be the driveshaft master so if there are any here help. Im moving the trans back up tomorrow the see if it helps. Quote Link to comment Share on other sites More sharing options...
redzedturbo Posted September 20, 2016 Author Share Posted September 20, 2016 Does any one know the stock 280zx pinion angle? i never measered mine and even if i did all my bushings were shot so yeah. Quote Link to comment Share on other sites More sharing options...
redzedturbo Posted September 20, 2016 Author Share Posted September 20, 2016 Wow you guys are overwhelming me with all your responses. I moved the tranny as far up in the tunnel as possible and was rewarded with 1/2 deg down at the tail shaft. Loosened all the rear member bolts shimmed here made things thinner there and the diff is 1/2 deg up. The only thing i noticed is the trans is slightly pointed at the passenger rear wheel and not pointed straight at the diff so i may have to slot the trans mount and shift it over to alighn it with the diff. After all this there was no more thumping shaft trying to get in to ride in the passenger seat. Now just slight vibe at wot. Its tolerable for now. Quote Link to comment Share on other sites More sharing options...
NewZed Posted September 20, 2016 Share Posted September 20, 2016 There's actually quite a bit of old stuff on the forum about how to set the transmission/motor and differential angles. Those are what matter. Their axes have to be parallel. The driveshaft angle is a side-effect. Use Google ans search "site:hybridz.org driveshaft angle", or "driveshaft vibration" and you might find something. Add "laser" and "alignment" and you'll probably find jmortensen's thread on a laser alignment method. Quote Link to comment Share on other sites More sharing options...
NewZed Posted September 20, 2016 Share Posted September 20, 2016 (edited) By parallel, I mean side-to side also, not just up and down. And don't forget your half-shaft u-joints, if you're using those. Or a bad CV joint. And the u-joints on each end of the driveshaft need to be in phase. In case you made it yourself. Might have missed it. Fun video - Edited September 20, 2016 by NewZed Quote Link to comment Share on other sites More sharing options...
redzedturbo Posted September 21, 2016 Author Share Posted September 21, 2016 after all my playing today my trans is at 0 and the diff is at 0 the drive shaft was i think 1.5 down but if i looked at the driveshaft from behind the diff the trans looked to the left of the diff so it is slanted horizontally some but i did not measure it. i can possibly slot the crossmember to get the trans inline with the diff and see if it helps. Thanks for the video. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted September 21, 2016 Share Posted September 21, 2016 Yeah you can slot it. Use a plub bob and hang it from the center of the damper and mark a line on the floor. Do the same at the output yoke and at the pinion flange. Use a string to see if all your marks are inline. Quote Link to comment Share on other sites More sharing options...
NewZed Posted September 21, 2016 Share Posted September 21, 2016 Not in-line, but shafts parallel. Crankshaft and pinon shaft. That's why people use the laser method. It can be difficult. Quote Link to comment Share on other sites More sharing options...
redzedturbo Posted September 21, 2016 Author Share Posted September 21, 2016 Im thinking the drive shaft is fine. The axle on the passenger side I THINK is the noise because it was making racket and changed pitch when i hit a dip in the road and made that shock compress. I looked at it today and if you grab the axle at the diff i can move it around some but the driver side is nice and tight no movement. The axles both feel clipped into the diff but the one has some play in and out as well as radial movement? Quote Link to comment Share on other sites More sharing options...
redzedturbo Posted September 23, 2016 Author Share Posted September 23, 2016 xnke and myself have the sloppy passenger side axle using the 300zx obx helical diff. Is it just us? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.