Jump to content
SAU Community

Choosing rear stub axles for diff upgrade

CowsWithGuns
 Share

Recommended Posts

CowsWithGuns Enthusiast

CowsWithGuns

Posted
Posted

Hello friends,

The other day I snapped an axle and have been thinking about upgrading diffs. Spent a few hours trawling through and have settled on upgrading to a nismo 1.5 way for my daily r34 gtt (I have no hopes for finding a nice helical from an s15 or late r34 any time soon, and if I'm gonna spend 1k+ on a centre it might as well be the 'best' one). Naturally I could go with 38420-RSS15-B5, the default for the r34 gtt, however; since my axle has snapped and I haven't sourced a replacement yet (seeing them $600+ second hand - gross!), I was wondering if theres a particular stub axle with readily available/cheap axles from newer nissans (e.g. 350Z) that are as strong or stronger than the stock r34 ones.

This option has broadly complicated things as I wouldn't know where to begin with determining what shafts have what bolt patterns/lengths to fit my car, so I was hoping someone has some pre-existing knowledge to share.

While I'm at it, it's a mystery my axle broke spontaneously (admittedly during a pull). The road was wet, and I only only push 230kw at the moment - any reasons why it might just give up and die like that with my relatively weak car and poor traction conditions?

robbo_rb180 Grand Master

robbo_rb180

Posted
Posted

What bolt axle do you have 2x3 or 5x1? 5x1 is the better design.
How low is the car and what angle are the axles at? 
What was the condition of the axle? plenty of people running the standard gear with a lot of power & semi slicks.

Best upgrade is the 350z but will require a diff swap and I think a hub swap to suit the outer splines similiar to gtr.

 

CowsWithGuns Enthusiast

CowsWithGuns

Posted
  • Author
Posted

I've got the 5x1. The car is lowered a fair bit - I see your point here. No idea, the cars seen a lot of action from the prior owners and lately from me so I guess it's a given eventually it wears out.

Regarding the 350z setup. I'm not down to go to the ~3.5 ratios the 350z runs. Currently I'm stock at 4.11, lowest I'd consider is 3.8. Getting a diff setup between 3.8 and 4.1 that accepts 350z axles and has a fully functional LSD (helical or mech) would be the dream. I have more research to do, thanks for your input.

CowsWithGuns Enthusiast

CowsWithGuns

Posted
  • Author
Posted

Couldn't edit my post, sharing my discovery here:

https://www.leesonengineering.com.au/blog/r200-350zgtr5x1-stub-conversion/

This mob will convert your stubs to accept both 5x1 and 6x1 patterns. With this option available down the track, I'm going to go with the recommended nismo LSD for my car which will come with 5x1. I was considering trying to get something with 6x1 stubs to 'future proof' my drivetrain but couldn't figure out whether the diff centres in those kits would be different or not, risking fitment issues with my diff housing.

GTSBoy Grand Master

GTSBoy

Posted
Posted

Balance almost certainly not important at that mass, diameter and location in the drivetrain. Balanced probably better, sure, but I'd be willing to bet the resulting vibrations from being left as is would be undetectable without reasonably precise gear.

Once thing I don't love is the vert close proximity of 2 of the holes. Not a lot of meat there. I know the flange to flange contact is still mostly there, but there would be a reasonable section of the axle's flange that overlaps the really close stub flange's hole - right where you would want to be transferring load. Again, probably about as important as the balance issue, but it still irks me.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • oHBoy.
      Starter motor replacment teeth count.

      By oHBoy. · Posted

      I had 3 counts over the last couple of weeks once where i got stranded at a jdm paint yard booking in some work. 2nd time was moving the car into the drive way for the inspection and the 3rd was during the inspection for the co2 leak test. Fix: 1st, car off for a hour and half disconnected battery 10mins 4th try car started 2nd, 5th try started 3rd, countless time starting disconnected battery dude was under the hood listening to the starting sequence fuel pump ect.   
    • GTSBoy
      Mistakes were made, my R34 Story

      By GTSBoy · Posted

      This. As for your options - I suggest remote mounting the Nissan sensor further away on a length of steel tube. That tube to have a loop in it to handle vibration, etc etc. You will need to either put a tee and a bleed fitting near the sensor, or crack the fitting at the sensor to bleed it full of oil when you first set it up, otherwise you won't get the line filled. But this is a small problem. Just needs enough access to get it done.
    • suko
      J50 clock date suddenly reset to January 1

      By suko · Posted

      The time is always correct. Only the date is wrong. It currently thinks it is January 19. Tomorrow it will say it is January 20. The date and time are ( should be ! ) retrieved from the GPS navigation system.
    • MBS206
      Mistakes were made, my R34 Story

      By MBS206 · Posted

      Buy yourself a set of easy outs. See if they will get a good bite in and unthread it.   Very very lucky the whole sender didn't let go while on the track and cost you a motor!
    • Kinkstaah
      Mistakes were made, my R34 Story

      By Kinkstaah · Posted

      Well GTSBoy, prepare yourself further. I did a track day with 1/2 a day prep on Friday, inpromptu. The good news is that I got home, and didn't drive the car into a wall. Everything seemed mostly okay. The car was even a little faster than it was last time. I also got to get some good datalog data too. I also noticed a tiny bit of knock which was (luckily?) recorded. All I know is the knock sensors got recalibrated.... and are notorious for false knock. So I don't know if they are too sensitive, not sensitive enough... or some other third option. But I reduced timing anyway. It wasn't every pull through the session either. Think along the lines of -1 degree of timing for say, three instances while at the top of 4th in a 20 minute all-hot-lap session. Unfortunately at the end of session 2... I noticed a little oil. I borrowed some jack stands and a jack and took a look under there, but as is often the case, messing around with it kinda half cleaned it up, it was not conclusive where it was coming from. I decided to give it another go and see how it was. The amount of oil was maybe one/two small drops. I did another 20 minute session and car went well, and I was just starting to get into it and not be terrified of driving on track. I pulled over and checked in the pits and saw this: This is where I called it, packed up and went home as I live ~20 min from the track with a VERY VERY CLOSE EYE on Oil Pressure on the way home. The volume wasn't much but you never know. I checked it today when I had my own space/tools/time to find out what was going on, wanted to clean it up, run the car and see if any of the fittings from around the oil filter were causing it. I have like.. 5 fittings there, so I suspected one was (hopefully?) the culprit. It became immediately apparent as soon as I looked around more closely. 795d266d-a034-4b8c-89c9-d83860f5d00a.mp4       This is the R34 GTT oil sender connected via an adapter to an oil cooler block I have installed which runs AN lines to my cooler (and back). There's also an oil temp sensor on top.  Just after that video, I attempted to unthread the sensor to see if it's loose/worn and it disintegrated in my hand. So yes. I am glad I noticed that oil because it would appear that complete and utter catastrophic engine failure was about 1 second of engine runtime away. I did try to drill the fitting out, and only succeeded in drilling the middle hole much larger and now there's a... smooth hole in there with what looks like a damn sleeve still incredibly tight in there. Not really sure how to proceed from here. My options: 1) Find someone who can remove the stuck fitting, and use a steel adapter so it won't fatigue? (Female BSPT for the R34 sender to 1/8NPT male - HARD to find). IF it isn't possible to remove - Buy a new block ($320) and have someone tap a new 1/8NPT in the top of it ($????) and hope the steel adapter works better. 2) Buy a new block and give up on the OEM pressure sender for the dash entirely, and use the supplied 1/8 NPT for the oil temp sender. Having the oil pressure read 0 in the dash with the warning lamp will give me a lot of anxiety driving around. I do have the actual GM sensor/sender working, but it needs OBD2 as a gauge. If I'm datalogging I don't actually have a readout of what the gauge is currently displaying. 3) Other? Find a new location for the OEM sender? Though I don't know of anywhere that will work. I also don't know if a steel adapter is actually functionally smart here. It's clearly leveraged itself through vibration of the motor and snapped in half. This doesn't seem like a setup a smart person would replicate given the weight of the OEM sender. Still pretty happy being lucky for once and seeing this at the absolute last moment before bye bye motor in a big way, even if an adapter is apparently 6 weeks+ delivery and I have no way to free the current stuck/potentially destroyed threads in the current oil block.
×
×
  • Create New...