I have a 2003 Z with the oem brembos and stoptech 2 piece rotors and have always experienced knock back. Gone through the typical changes of wheel bearings and knock back springs with no success.

I drove a 370z recently which has the Akebono calipers and tried to induce knockback as I would in mine and found it had very little to none. So i thought that nissan must of upgraded the wheel hubs/bearings.

Searching online Z owners are saying that the 370z has upgraded wheel hubs but when you look at the part numbers on courtesy parts the 350z and 370z list the same part numbers. (correction the part numbers are different)

40202-1EA0A- 370z
40202-AL56C- 350z

Anyone have further info or a picture of the 370z wheel bearing handy?

 

Even better, FWD Nissan Morano hubs. Just get the rear hubs from it and install them up front. It even works with ABS, little tip i got from Fontana Nissan.

 

I don't have any knock back on my Z with either the OEM brembos or the my Stoptech brakes, but have heard about people who have it bad.

 

If they are indeed different (and better) that would be awesome. Do you know which murano year or model ie: Z50 or Z51? I did a quick lookup on Nissan fast and this is what came back.

Z51 - 43202-JP20A- 4WD
Z50 - 43202-CA100- 2WD
Z50 - 43202-CA000- 4WD

I don't have the Z51 2WD listed in my copy of Nissan FAST so was unable to check. Not sure if it even exists.

Here are some possibel pictures of the wheel hub off a Murano. The thickness of the face plate where the studs are don't look that promising

 

Noob question, What is "knock back"?

 

See:
http://www.stoptech.com/tech_info/wp_knockback.shtml

 

^thanks...

 

SUBSCRIBED! I got two sets of knockback springs in. They are working for me now. Although now that I'm down to about 25% brake pads it's noticible again. But at this point its really time to get new pads.

 

Z50, rear hubs off the 2wd. Its what Fontana Nissan runs on their race car.

 

Cool.. thanks for the clarification

 

for the fun of it i compared the 370 hubs to the 350z. The 370's carrier bearing is about 10mm bigger than the 350's

Also does anyone know if there are any kits on the market that use radial calipers but clock the caliper to the 3 o'clock position on the 350z.

 

Has anyone tried this yet and noticed an improvement? I'm getting pretty bad knock back and I'll probably need new hubs soon anyways.

 

To ensure that no one buys the Z50's wheel bearings on blind faith, I can tell you that they are totally different than the oem Z33.

Well they will fit. The carrier bearing and mounting bracket appear to have the same dimensions and layout but the wheel bearing will offset the wheel about 15mm to oem.


Anyone want a pair of new Z50 hubs going cheap

 

i asked a guy at fontana nissan, and he said murano hub and z33 hubs are totally different. I checked the flange offset and all that on rockauto and they have different numbers. IIRC, he said the racing team is still in process of testing it out on z33.

Maybe the murano hub appears to be stronger because they offset the wheels more?
I was hair close to placing an order for murano bearings but i waited a day and called the fontana guy. And decided to go with OEM on one side and Timken on the other side.

 

I get significant knockback on my stoptechs. I'm going to change out my hub assembly because its fairly cheap and easy to do myself. Right now my solution, as I'm sure the rest of you guys, is to give the brakes a little tap before the braking zone so I have some pedal when I really need to brake. It's easy enough to do, but if I can avoid it I will.

I'm trying to understand why some Zs get knockback while others don't. Is it that the non-knockback guys aren't pushing it as hard as the knockback guys, or there is a wide tolerance in the oem part quality so that one oem hub is different enough from the other that one gets it and the other doesn't.

Also a guy at Performance Speedtech suggested flipping over the washers on the two piece rotor. He said that the washer is conical and "preloads" the rotor. I haven't tried it yet, but I might if getting new hub assemblies don't work.

As for the 370, My father has one with the sport package that includes the Akebono brakes. He has absolutely no issues on the street or track.

 

New hubs won't do anything. Never did for me anyway. My knockback was so bad that it happened sitting in the parking lot.

Only one thing that really worked for me, Knockback springs. I put double sets in each piston. The springs cost 20-25$ EACH. I think I got them through www.zeckhausen.com but can't find them there right now. Or just call up stoptech and ask where you can get the springs from.

Flipping the washers did help some but the springs completely solved the problem. Also with flipping the washers your rotors will become loose which isn't a bother at the track but on the street it can be irritating.

 

Was it a pain in the butt to disassemble your calipers and install the springs? (I assume that's how you do it)

The only reason I want to change the hub is that I banged a wheel pretty hard against one of the many concrete medians in College Station. I damn near drove over it because it was at night, I never saw it.

 

It's time consuming because you'll need to pull the caliper off the car. But get yourself a break piston puller and put some multipurpose greese on the piston seals when you put the pistons back in and it's not too bad.

I've done it twice now and they need a rebuild again before I get on a track.

However having the springs in there can make it tricky when you go to replace the break pads. Although the springs aren't that strong so the pistons don't tend to try to slide out too much.

This hit pulled out my alignment but the hub was fine. Although that was on the rear of the car.

http://youtu.be/7GDNssw8UXA

 

Sorry to jump in here ... But what version of fast are you using? I have a version that only goes up to around 2000 and I can't look up my 03 z
Any info would be greatly appreciated .

 

post is 5 years old ^^^^