The GKTECH 240sx/Skyline to 350z/370z Diff conversion bushings allow you to bolt in the stronger 350z/370z/G35/G37 differential to your 2 bolt R200 S14/S15/R33/R34 subframe. The bushings are CNC Machined from 6061-T6 aluminium and require no further modification to the subframe, just simply press the two bushings into the diff, while pressing the other in the subframe.You will notice there are two options to choose from, most commonly people have the OEM single bolt cover, which comes as shown in the product photo. To help strengthen the rear support of the diff and counteract the single stud we do now also offer a diff brace (optional item). The other selection is for two bolt Z33/Z34 diff housings, which will come with two front bushings and two rear bushings. NOTE: Upon fitment, please check driveshaft (CV/axle) length to ensure there are no possibilities of the driveshaft (CV/axle) overextending or driveshaft (CV/axle) compression, which may lead to failures. NOTE #2: The option "Z33/Z34 diff conversion secondary bush (for S14/S15 subframe)" is for those that are already running the conversion bush set (3pcs) and only want to purchase the 4th bush when running one of our CNC machined billet diff covers or the Greddy dual stud diff cover. FAQS Will this fit my car?We can only confirm fitment for the vehicles listed above under "vehicle compatibility". If your car is not listed there, then we don't know if it will fit.Do you make these to suit other cars?We only sell the parts listed on our website. If it's not listed on our website, then we don't sell it. Sorry.What's the advantage of using the GKTech 350/370z diff conversion bushes?The 350z/370z/G35/G37 diffs are becoming more readily available and are newer than the 15+ year old diffs people use now. They also have driveshaft (CV/ axle) sensors which are great to use for calculating wheel speed. The stub spline that goes into the diff center is the same as R33 GTR being a 31 spline. As opposed to the R32 GTR diff being 30 spline and the R33 GTS-T diff being 29 spline. The pinion gear thread is also larger on these diffs then any S/R chassis diff. They also use Rzeppa style driveshafts (CV/ axles), which are significantly stronger as oppose to the Tripod design S/R chassis have which are weaker.The driveshafts of the all the CV/ axles excluding the 370z also directly bolt up to S/R chassis wheel hubs. The 370z shafts have a GTR spline output to the rear wheel bearing/hub, meaning the wheel bearing/hub would need to be changed to the GTR equivalent.What modifications are required, is this hard to fit?You will need to redrill your diff flange to suit your tailshaft bolt PCD, which can be done relatively easily. Then press the bushes into the diff and subframe. Please take note of which direction the rear bush is to be facing based on the position of the diff stud before pressing the bush in.Is there anything else needed for installation?You will need to purchase the diff itself. Apart from that, the OEM hardware can be used as the bushes will arrive as shown in the product photo.Can I install this myself? If so how long will installation take?Yes, it is relatively straightforward. Once the subframe is out it should take around 45 minutes.Do these bushes offset where the diff mounts in the subframe?No, the bushings have been designed to align the diff in the center of the subframe.I keep breaking the teeth off my crown wheel, will this diff be strong enough to stop that happening?No, the crown wheel and pinion and the same between S/R/350z/370z/G35/G37. That is why they are still called an R200.What sort of ratios do these diffs have?The 350z/370z/G35/G37 diffs have a wide variety of OEM ratios which can be seen here;Z33 - MT - R200 - 3.538Z33 - MT - R200V - 3.538Z33 - AT - R200V - 3.357Z34 – MT – R200V – 3.692Z34 – AT – R200V – 3.357G35 - Sedan - AT - R200 - 3.357G35 - Sedan - MT - R200V - 3.538G35 - Sedan - AWD - AT - R200 - 3.357G35 - Coupe - MT - R200V - 3.538G35 - Coupe - AT - R200 - 3.357G35 - Coupe - AT - R200V - 3.357G37 – Sedan – AT - R200V – 3.357G37 – Sedan – MT – R200V – 3.692They also have aftermarket support with ratios from 3.9, 4.1 and 4.3 VEHICLE COMPATIBILITY NISSAN R32 SKYLINE GTRR33 SKYLINE GTRR33 SKYLINE GTS-TR33 SKYLINE GTS4R34 SKYLINE GT-TR34 SKYLINE GTRS14 240SX/SILVIAS15 240SX/SILVIA USER GUIDE(S) INSTALL VIDEOS