75 280 Rear Suspension Work & Disc Brake Conversion (MilkFab)

[HusseinHolland]

Slow going today. All I got done was the bearing & spindle/hub assembly, and a couple odds & ends. 

Besides pressing the outer bearing onto the spindle first, I didn't find the FSM particularly helpful in terms of assembly directions. It is important to only apply pressure to the side of the race being inserted, to prevent bearing damage, but I couldn't see anyway to press the spindle with bearing into the hub that didn't involve applying load to the inner race as well. I ended up just tapping the outer flange evenly around the circumference to seat the outer race of the outer bearing in the hub. To install the inner bearing in the hub and on the spindle, I just used the old bearing, so both inner & outer races were loaded evenly.

Before I did any assembly I did another dry run with the old bearings to determine if I needed to cut it down to clear the CV. I did need to. Took the nuts off, cut off the shoulder.

Reassembled. Clearance is good here - about a 1mm off the CV inner cup

 

Both distance pieces were marked B

pressing the inner bearing, after greasing the backside of the inner & outer bearing cavities & installing distance piece. Used an old camber plate from my 98 XC to apply load to inner & outer races, and still clear the spline shaft

#2

inner grease seal going in. It is pressed all the way in, according to the FSM diagram , just doesn't look like the lip is going to have much surface contact with the inner hub flange

I then torqued the nut to 195ft/lbs. drag feels even, no end play. I have no way of measuring 3.9in/lb. My 1/4" drive Snap-on torque wrench is not accurate below 10in/lb

I had notched the nuts, so I could tack weld them to the spindle without creating a weld- mound that would interfere with the CV cup clearance.

#1 MIG welded. In the unlikely event I ever need to remove them again, I can cut the tack weld as easily as cutting the stake shoulders of the original

#2

I found the wheel studs I bought for the rear were actually 2.25", not 2" as listed. Test fit the spindle with a rotor to check depth. I had to cut them down to 2" or the wheel nuts won't seat

after

Another catch - with the larger OD CV flange, clearance off the Strut cast base is an issue - I had looked at that, but without it being assembled, there was no way to be certain what would be best approach. I opted to use press-studs, similar to wheel studs, just M10x1.5

They were longer than needed, so I trimmed about 1/4" off, as assembly on the car may become an clearance issue

cut

After that I test fit the MilkFab brake caliper brackets & swapped out the eBrake as per their instructions. 

parts removed

MilkFab eBrake bracket positioned, cable levers reversed L/R as per their instructions

checked offset with a rotor, everything looks good

Going to be out of town until next Friday, so have to wait to get it all back in the car.

 

 

Edited July 23, 2023 by HusseinHolland

[Zed Head]

The bearing pressing has been discussed off and on around the internet.  The procedure is counter to normal but it's what Nissan says to do.  The question would be "how much force is necessary to get the bearing races seated?"  The final torque value is only on the inner race and distance piece, not the balls and races.  I haven't done one so don't know how hard it is to push the races in during installation.

[HusseinHolland]

2 hours ago, Zed Head said:

The bearing pressing has been discussed off and on around the internet.  The procedure is counter to normal but it's what Nissan says to do.  The question would be "how much force is necessary to get the bearing races seated?"  The final torque value is only on the inner race and distance piece, not the balls and races.  I haven't done one so don't know how hard it is to push the races in during installation.

That's kinda what I figured - the energy required to tap the outer bearing race(by way of the flange) into the hub is far less than the load it will see in use. The inner bearing is pressed uniformly, the way I did it, so not an issue there.

 

 

 

Edited July 23, 2023 by HusseinHolland

[Captain Obvious]

On 7/22/2023 at 9:30 PM, HusseinHolland said:

It is important to only apply pressure to the side of the race being inserted, to prevent bearing damage, but I couldn't see anyway to press the spindle with bearing into the hub that didn't involve applying load to the inner race as well.

One time when I was assembling rear bearings, I went through all sorts of gyrations to prevent assembly force from going through any of the bearing balls. I've since decided that it wasn't worth the effort.

On subsequent jobs, I've found that the press fit category of the outboard bearing race into the hub bore was a relatively light press fit and didn't require a lot of force. I'm assuming that Datsun designed it that way.

[HusseinHolland]

Still don't have the rear back together - I forgot I needed to clean (power washed, dried, rinsed with turps, wire brushed) & apply the 3M stone guard (1 can) & Undercoat (1 can) first

Did the back off the Gas tank while I was at it

 

[HusseinHolland]

So.... I got some work done on the rear suspension & CV conversion. First, I started to assemble the rear struts only to find the spring was waaayy to short - then I figured out I put the rears on the front - I'm used to cars where the front spring is typ[ically longer than the rear, and I just assembled it that way. SO, I had to remove both front struts, remove the .002 springs & put the .001's on instead, then assemble the rears with the 002's. The fronts (Eibachs) are so short that the upper seat is loose at full drop.

Didn't get many pics today, it was so f'ing hot I was dripping all over everything. Only got the right side in.

Checked the right axle & stub against the 300ZX T right axle (#NI8442), overall the later axle is longer when fully extended. With it installed (with outer CV now at it's inner end of travel), I had about 1/8 - 3/16" slack between the flange & CV, so no bind will occur. I was going to change the axle seals in the diff, but the ones I got off RockAuto are the wrong dimensions - with the axle inner stub out, I got the numbers off the seal R15 35 55 11

The seal I have is clearly too small (when measured). I went back with the dimensions I now have off the seal & figured out the National 711070 matches the 35/55/11mm dimensions. I have no obvious leaks from the seals, but I really wanted to do them now. The way these axles are installed with studs on the flanges, the hub spindle bolt has to be removed to get the axle out

right axle in the diff, located in the outer flange

 

clearance at full drop

clearance at normal ride height - not very scientific, and it's unclear form the pics, however there is much more play as the axle lifts 

getting the clevis pin back in was fun - I had to double-nut the spindle & work it back & forth on it's axis to get the pin to drop, then I also had to knock the spindle fore/aft to get it to fully seat in the housing

 

Edited July 31, 2023 by HusseinHolland

[HusseinHolland]

Yesterday I fitted the left axle ('87 300ZX T, #N18435) & strut assy. I found that the left axle had almost no play in the outer CV at full drop. I can't imagine it would work without binding using one of the flanges as intended, esp. w/ stock springs, since that would drop the hub even further.

Left inner stub. They are the same length, just aftermarket has a shorter innermost spline section and deeper outer seal seat shoulder.

 

left axle seal was also not leaking, so I'm just going ahead without replacement

installing the strut assy - used my jack to lift the assy. in place, so I could secure the strut top plate in the tower

once the top was secured, I could position the spindle hub & insert the spindle/bolt and clevis.  Not fun. The elements do not readily align, so the shoulders on the spindle can catch on the bushing sleeve in the control arm. This side took several tries to get it in place.

Spindle & axle in place

With that done, I started on the brake install. (re-drilled) '88 300ZX T Rotor then (Mustang rear '05-2014) caliper hanger installed, all good so far...

Then I found a couple issues. I had never checked the kit listing to see if the kit worked with modded setups - it doesn't mention whether it only works with stock setups & I didn't think to ask at the time. The eBrake bracket will not clear the CV flange. I'd be curious to see a pic of it in relationship to the stock U-Joint shaft flange, as it seems that the cable bracket would still end up pretty close to the rotating flange.

Needs to swing inward I'd say at least 3/4" from here to get the upper caliper retaining bolt into the caliper slider pin. I'll have to cut & weld the bracket to make this work.  Angle and offset relative to the actuating lever can't change too much or it will bind the cable, and/or just not operate as intended. I've emailed MilkFab to see if they have suggestions.

This also seems to be an issue - Milkfab directions just say to attach the stock cable end to the lever. I could not see how the different designs could interface - now looking at the pics, I'm thinking he wants the clevis pin looped over just the outer ear of the lever. There are no comments in the instructions or photo documentation to assist in this, which would have been helpful. I'll work on this today.

Edited July 31, 2023 by HusseinHolland

[HusseinHolland]

Resolved the eBrake lever issue. Figured out I could just redrill the axis point, and gain the necessary clearance off the flange

Rotated the flange on the back of the caliper to mark the centerline, drilled a new 1/4" hole just outside the existing 

Reassembled after confirming offset clearance 

Edited August 1, 2023 by HusseinHolland

[HusseinHolland]

Cable attaches as I thought after looking at the pics I took

Getting all the cables / hoses  routed nicely. Used a vacuum- bleeder after this to get the rears bled (Dot 3). 

adjusted the cable to get enough slack. Looking online, there are ppl using pliers to turn the rod - I realized that the rod end is 8mm, just have to turn it

 had dropped the heat shield to get better access - so I removed the Cat heat sensor & shield while I was in there

Volvo grommets to fill that & another hole

problem with MilkFab cable bracket - it flexes significantly when cable is operated. I've emailed MilkFab about it

car in the air, did some more power washing before putting wheels back on

wheels on, after driving to settle the suspension - when I first took it off the stands, it looked like monster-truck arch clearance. Still would like it lower, but roads around here are not great & the town had speed bumps all over. Feels so much better on the road now, it was horrible with all the worn parts.

 

Edited August 1, 2023 by HusseinHolland