Skylane rear end for Q G50

[Johnny Rocket]

I just purchased a rear end from a member that is said to fit in a G50. Alhough all the mounting points look correct the casting is about 1.5 inches too short. That measurment is from the two forward mounting bolts to the end of the casting. It was indicated that this was an easy swap as I was looking for a 4.08 gear ratio. Supposedly some other member or members have done this swap?

It would appear that the driveshaft would have to be lengthened or a new one built at of course great expense.

I would like to hear from ANYBODY who knows more than I do about this swap? I am hitting my head over this one for not having done more research.

Thanks

[maxnix]

Maybe AZhitman will show up. I think he did this swap. There are a couple of threads on the swap. A couple more on why it isn't such a good idea for everyday use.

I think the fitment may have something to do with the pilot shaft.

[Johnny Rocket]

pilot shaft?.or pinion gear.....?All the mounts look the same......the rear end is short at the pinion .....from the forward mounting bolts to the end of the castings........

[Trumpkin]

Some pics might help. What kind of rear is it?Are you sure its from a skyline? The swap does work-if it's the correct rear. On most you do have to change the front pinion. You will also need a trans gear to offset you speedo.

[maxnix]

My memory is not complete on this point. Might try to email Greg (AZHitman).

[Johnny Rocket]

My memory is not complete on this point. Might try to email Greg (AZHitman).

Wes is going to download some pics I sent him....he thought the part number was correct.......there might be a difference in the tc rear vs the non tc rear.

Also there are two sensor wires at the rear end at the back..on my Q I have only the one in front.

My question is does one sensor run the TC and the other the ABS.....or?

[Johnny Rocket]

I cant find any decent threads on this subject. Only 1 and James Most did most of the talking. I have contacted him and he even is somewhat confused as to what he has under his car.

The case on the r32 gt rear is different for sure. Looks like you could bolt it in but even changing to a Q yoke probably wont do it.....the Driveshaft will be too short.

There just is not enough info on this swap to glean any real good information that a person might use to make this a no brainer.

Its going to be a brainer....

[NOR*CAL 916]

i have done this swap myself, ive had it for two years and its worked great. The diff i have is off a skyline R-32 GTR which is the only one that would fit the Q45. It is a direct bolt in and it is a 4.11 gear ratio and not the 4.08 everybody says it is also its a clutch type diif compared to VLSD the OEM Q45 came with. There is a few things to consider when doing this swap. The skyline pinion flange that bolts to the driveshaft has to be removed and replaced with the Q45 pinion flange. The Q45 has the ABS sensor ring on the pinion flange shaft which is why the Q45 diff is longer. remove the ring and install the flange. I did this with an impact gun to take off the flange nut and a puller to take off the flange and the same puller to take off the ABS ring off the Q45 flange shaft. ABS will not work after this swap unless you find a way to attach corresponding sensors to the skyline diff. The skyline ABS sensors are at each output shaft so you would need to have two sensors. Also since GTR skylines have HICAS four wheel steering the Skyline diff has a mounting point on top for HICAS shaft supports, i cut off about an inch of the top of the diffso it can fit. The diff swap is very noticable around town driving, it is much snappier when accelarating and passing on the freeway is a breeze but MPG WILL suffer on the highway my RPM hovers around 3k when it used to be around 2.5k on the freeway.

[Johnny Rocket]

Nor Cal thanksHere is another question....how can the Q driveshaft work? The casting is shorter and the companion flange on the skyline is quite different. So between a different casting and a different flange how does the driveshaft length work out?

Since I have been investigating this I see that powertain ( eric) says he has an adaptor for the skylane flange so you can use a real U joint... but a custom driveshat will be required. I will send some pics to your email.

[Johnny Rocket]

Q45 has the ABS sensor ring on the pinion flange shaft which is why the Q45 diff is longer

The above sentance would indicate that this is not part of the rear end........but careful examination of the pics I sent you will show the rear end length extension is part of the casting. Its not something that you can take off and make the rear end match the length of the Q...unless I am missing something?So the Sensor ring in my car is not something you can take offf...see the pics I sent you.......I would post them on here but cant figure out how to do this yet...to new to this forum stuff...

[maxnix]

The Q45 has the ABS sensor ring on the pinion flange shaft which is why the Q45 diff is longer.

I believe this is only true of the non-TCS cars.

[Johnny Rocket]

I have a non TC car.....the rear end has the area cast into it...making it about 1.5 inch's longer........maybe a tc car the rear end is shorter like the r32 gt diff?

[NOR*CAL 916]

The pics you sent me of your Skyline diff is the same as mine, once you take off the skyline campanion flange and replace it with the Q45 companion flange then it will all line up. There is no need for a new driveshaft the Q45 driveshaft will work with the Skyline differential. The only issues is the ABS,companion flange, and the threaded hump on top of the diff that ypu have to cut off i used a die grinder to cut it off other thatn that its bolt on.

[Johnny Rocket]

Thanks for all who had some definitive answers. I am still not seeing the driveshaft working as of yet but I am going to throw it up in place and see what happens.

I know this is not the MOST popular addtion to your Q's but this engine really likes to be RPM happy.......and caring about gas mileage and a few extra rpm is not what this car is about to me anyway.

I think this car should be driven hard per Wes..

Thanks for some clarifications and I will give you a report back...

[Johnny Rocket]

i have done this swap myself, ive had it for two years and its worked great. The diff i have is off a skyline R-32 GTR which is the only one that would fit the Q45. It is a direct bolt in and it is a 4.11 gear ratio and not the 4.08 everybody says it is also its a clutch type diif compared to VLSD the OEM Q45 came with. There is a few things to consider when doing this swap. The skyline pinion flange that bolts to the driveshaft has to be removed and replaced with the Q45 pinion flange. The Q45 has the ABS sensor ring on the pinion flange shaft which is why the Q45 diff is longer. remove the ring and install the flange. I did this with an impact gun to take off the flange nut and a puller to take off the flange and the same puller to take off the ABS ring off the Q45 flange shaft. ABS will not work after this swap unless you find a way to attach corresponding sensors to the skyline diff. The skyline ABS sensors are at each output shaft so you would need to have two sensors. Also since GTR skylines have HICAS four wheel steering the Skyline diff has a mounting point on top for HICAS shaft supports, i cut off about an inch of the top of the diffso it can fit. The diff swap is very noticable around town driving, it is much snappier when accelarating and passing on the freeway is a breeze but MPG WILL suffer on the highway my RPM hovers around 3k when it used to be around 2.5k on the freeway.

Hey Nor cal......where are you getting the 4.11 gear raio from?...how about a 4.37????!!!! on the one I purchased from a member represented as a 4.08

[Johnny Rocket]

The pics you sent me of your Skyline diff is the same as mine, once you take off the skyline campanion flange and replace it with the Q45 companion flange then it will all line up. There is no need for a new driveshaft the Q45 driveshaft will work with the Skyline differential. The only issues is the ABS,companion flange, and the threaded hump on top of the diff that ypu have to cut off i used a die grinder to cut it off other thatn that its bolt on.

I measured and measured till I am blue in the face.......changing the companion flange will not get me back to the driveshaft period........I would love to see the bottom of your diff? in the companion flange area back to the two front mounting bolts..!!Has to be different........has to be

[mxr662]

This is the same as NOR*CAL 916's diff.

[Raxephon]

This is the same as NOR*CAL 916's diff.

That looks a lot like a Z32 300zxtt flange on that differential.

[Johnny Rocket]

Their no room for the Q ABS pickup wheel in the skyline rear end....must be front wheel drive or something.....

The companion flange coupler will not phisically fit into the new housing as the ABS teeth need a cavity to fit into.........no such cavity in the new rear end...

Even if it did fit the driveshaft would be too short..

Big mess and not enough info........thats what I get for trusting this guy.....you should be able to trust a forum member?

[NOR*CAL 916]

If you got a 4.08 gear ratio diff i think you got a 300zx tt rear differential. It is not the same and it wont bolt up to our Q45. Sorry man i think you got the wrong differential. I noticed that your differential has a VLSD (viscous limited slip differential) the R32 GT-R Skyline with the twin turbo RB26DETT has a 4.11 gear ratio and it is a clutch type differential and not a VLSD my diff has the orange sticker that says ''LSD'' instead of VLSD. I sold one to our fellow Q45.org member (mxr662) about a year ago he has the exact same differential as i do.

[Trumpkin]

If you got a 4.08 gear ratio diff i think you got a 300zx tt rear differential. It is not the same and it wont bolt up to our Q45. Sorry man i think you got the wrong differential. I noticed that your differential has a VLSD (viscous limited slip differential) the R32 GT-R Skyline with the twin turbo RB26DETT has a 4.11 gear ratio and it is a clutch type differential and not a VLSD my diff has the orange sticker that says ''LSD'' instead of VLSD. I sold one to our fellow Q45.org member (mxr662) about a year ago he has the exact same differential as i do.

So which diff is better? lsd-vlsd?

[Infinitiguy19]

I prefer VSLD, but its harder to control than LSD.

[Trumpkin]

I was looking for more of a tech answer. but thanks non the less!

[Infinitiguy19]

You can wait for Q45Tech to come in or read this: http://zilvia.net/f/tech-talk/869-lsd-vs-vlsd.html

Or Google it.

[Raxephon]

VLSD is good for normal everyday use.

Clutch based LSD is typically better if you plan on putting a lot of power to the wheels.

[Johnny Rocket]

Both the rear ends I NOW have the orange sticker LSD viscous

What did the clutch style LSD come in?

[maxnix]

So which diff is better? lsd-vlsd?

Clutch type LSD is usually quicker adting thatn VLSD, but requires more maintenance.

[maxnix]

What did the clutch style LSD come in?

BNR32 and I believe BNR33 and BNR34.

[elwesso]

Im pretty sure the R32 and R33 had the VLSD and the R34 had the clutch type because the R34 had the electronic AWD or something crazy..

Next post will have some pictures that Johnny sent me, he should be able to explain whats going on.

[elwesso]