240sx ring and pinion gear on a q45 differential

[r3v_v3ng3]

as i'm waiting for the extended lugs, i want to know if a 240sx ring and pinion gear will fit on a q45 differential?

my research: (93) q45 have a r230 casing but a r200 internals. 240sx diff is r200 so i'm guessing it may fit.

reason i want to know is that i don't want the q45 lower gear (3.6). the 240's ratio (4.08) is more suitable for my driving. i don't go to the freeway often and not planning to have massive horsepower. i already have all the necessary parts to swap the rear end. just wondering if anyone tried it before and does it work or not. that way i won't tear both diff up to try to find out.

also i seen a post on the classified and the seller stated that it will work. zerothread?id=335152

anyone else can confirm this?

[r3v_v3ng3]

anyone?

[r3v_v3ng3]

since no one can confirm this. i went ahead and tore down both differential. i will keep you guys updated whether it works or not

[Makenski]

so whats the word?

[r3v_v3ng3]

it works. its time consuming but its well worth it. you have to get one of the input shaft machined. get to keep the stock gear ratio and the abs

[BHayes_S13Coupe]

I want to do the opposite, and use the q45 ring and pinion. You still have the q45 r/p lying around??

[r3v_v3ng3]

I want to do the opposite, and use the q45 ring and pinion. You still have the q45 r/p lying around??

yes i do but the pinion gear is still in the case.

[placham]

Looks like I'm a little late.

But here is my 2 cents

I'm running a Q45 VLSD in my 240sx. I used the stock 240sx drive shaft flange on Q45 pinion. Same size and spline count. This could be some useful info for people looking to go with Q45 Diff. As some may know until know most people use to drill the Q45 bigger pinion flange with correct 240sx drive shaft bolt pattern. If you use a puller (which makes it a whole lot easier) to remove both pinion flanges, and throw the 240sx flange on Q45 diff. It will save you bunch of time with drilling and tracing bolt holes.

Knowing this, I wouldn't be surprised if the guts are interchangeable. And since the covers fit god knows how many different variation of this diff. But axle flanges are differential carrier specific(part where your ring gear bolts onto), come in different sizes. Q45 being the beefiest of them all.

Hope this helps out someone else interested in this.

Oh by the way to run Q45 diff you need, Q45 driver side axle, and 300zx TT driver side axle, and the Q45 or 300zx TT wheel hubs (5 lug), have bigger bore and spline count for axle shaft then 300zx N/A, J30 and 240sx.

300zx axle on driver side, and Q45 axle on pass side.

[r3v_v3ng3]

yeah. while i was swapping the pinion flange. i was like "why didn't the guy(on the post about q45 diff into 240sx) just swap out the flange instead of drilling extra holes"? but its a good way to point that out.

[placham]

I was too lazy to check first, and I actually drilled all 4 holes into Q45 flange. I would have to enlarge them to work. But I was like wait I will try the 240sx flange. I tried J30 flange onto Q45 earlier and it fit, J30 by the way is same as 240sx flange.

Guess what 240sx did fit onto Q45, I was so mad. But it's all good, you learn from your mistakes

[r3v_v3ng3]

true that

[compactfean]

Sweet! What part did you have to have machined? Can you be more specific please.also...your talking about using r&p from open end diff right?

it works. its time consuming but its well worth it. you have to get one of the input shaft machined. get to keep the stock gear ratio and the abs

[compactfean]

Bump...anyone?

[r3v_v3ng3]

cant remember on top of my head but when i did it, i just swapped the q45 diff in the stock 240 housing using the 240 r&p but i had swap the bearing left to right. once you do this one of the output shaft cant remember which one, will stick out about 1/4 of an inch and you have to go to a machine shop to to shorten the sleeve about 1/4 of an inch and cut 1/4 inch off the end of the input shaft. sounds complicated but once you swap it over you'll understand what im talkin about

ill check out the car tomorrow if i remember
Modified by r3v_v3ng3 at 11:16 PM 12/20/2009

[compactfean]

Actually sounds simple. So if I'm using q45 housing. Then r&p should drop right in.

[r3v_v3ng3]

i would rather use the 240 housing its more easy so you dont have to transfer the pinion gear, they are the same housing. so you just have to transfer the 240 ring gear to the q45 diff

[compactfean]

Its worth it for the stronger axles.otherwise I'd just go j30. Thanks for the info though considering this thread is like 6 months old.

[r3v_v3ng3]

Its worth it for the stronger axles.otherwise I'd just go j30. Thanks for the info though considering this thread is like 6 months old.

i got a good deal on it so thats why i did it. my friends sold me a whole rear subframe from a q45 (hubs, brakes, diff) for 200. i already had 300zx rear brakes/hub. all i needed was the diff and axles. i then sold the rear hubs with brakes to my friend and helped him install the q45 brakes/hub on his s14 for 200. i just had to buy a 300zx TT driver axle for $50 and $20 on machining. so for me it was worth it but my ka-t is not even putting out massive power for the axles to handle. oh yeah no problem maybe i'll make a thread on how i did it step by step for the people that got a good deal on a q45's

[r3v_v3ng3]

so if you dont get a good deal on it, its better off getting j30's.