Nissan Throwout Bearing Collar
Comparison Measurements < in millimeters >

NOTE: This page is a "Work in Progress" last updated on June 29, 2003, Not all information documented has been posted nor double checked for complete accuracy. Use information on this page as a guide only.

05/05/03 Update: After some research, I believe the above illustration and measurements are not accurate enough to rely on. Above measurement overlays on photos are correct and transmission labeling is probably correct, but I have since discovered that Nissan produced more TO bearing collars for Z cars and related L series engines than is shown in above photo. Please read Jan 23, 2002 - First Observations post below to learn more about this documentation project and what new photos and facts are being prepared for this ZP Tech Section on interchangeable clutch and transmission parts. ----Eric Neyerlin

Jan 23, 2002 - First Observations

As time has marched on since the first Z car's introduction and more and more odd ball collars from other L series engines and trannies have found their way into self serve junk yards and then into your garages, this issue has become more complex to keep track of. Because I could no longer hold all the variable answers in my head to answer customers with, I decided last month to start working on a complete documentation of all swapable clutch and tranny components that may be involved when swapping trannies from different Z car years and models.

Last month I published a preliminary comparison photo of 4 collars with bearings and specs attached that I had found on my shelves at the shop. Unfortunately, one collar and bearing proved to be undocumented and one of my measurements incorrect.

Further research has now turned up at least 4 different Nissan Z car collar lengths and part #'s with one other in question. To make matters worse, I reasoned that possibly many non-Z car collars from other Nissan/L Series eng/tranny cars and trucks may have been filtering into the scene and making matters even more confusing.

It soon became apparent that all Nissan clutch components and parts #s would have to be documented better plus other related components, in order to make my Tech article useful to a wide Z owner audience so I went back to square one and started over again.

With the generous help of John Vanek and Dave Watkins of the Z Doctor in Richmond, CA, I now have excellent comparison photos, part numbers and production date/yr/model specs taken and assembled for the collars, forks, 2 of the 3 flywheels and 1 of the 2 types of slave cylinders produced for Z cars between late 1969 to mid 1984 that will relate to the topic at hand. Eventually, I hope to add photos and specs for all clutch master cylinders, master vacs, speedo gears, etc.

SIDE NOTE: an autocrosser from WA state recently sent me 3 Excel spreadsheets setup to calculate all kinds of Nissan tranny and differential "what if" final drive ratios and RPM/torque optimizations possible from all Z car tranny and rear end swaps. Eventually, these custom spread sheets and several web viewable tables of specs will be published for all to make use of that will tie into the topic we are discussing here.

OK, so what components to use? There is more to it than I can write now, but John Vanek, of the Z Doctor, told me that the best guideline for coupes (not 2+2 cars) is to purchase all matched Nissan clutch components (pressure plate & disk) for either a 4 or 5 speed and use the original T/O collar, bearing, fork, slave that originally came with the 4 or 5 speed you are swapping in. The curse begins when you mix up the hdwe from 2 different types of trannies you have kicking around your garage. Hopefully, after I get my article and comparison photos up with attached measurements, Z owners will be able to use it to figure out what hwde in hand originally fit what?

Since I first published my first collar comparison photo I have received several interesting comments from the experience of others that relates to a few lesser known swap issues, such as the fork pivot ball height adjustment and aftermarket T/O bearing variable specs and master cylinder bore size, that also may lead to clutch problems down the road. I'll try to include their advice into the article as time goes on. If any of you wish to send me comments or suggestions as to what other topics and specs to include, feel free to do so.

Eric Neyerlin - owner of  .com