QX70 6MT Research Questions

[mnz4]

TLDR: Questions are bolded.

Sorry if this is beating a dead horse. I've done as much homework as I can without starting to buy parts so I'm hoping the community can help fill some gaps.

I will be picking up a QX70 as my next vehicle and will enjoy it as is for a while. I’m coming from a heavily modded WRX wagon and want something a little more comfy without giving up all the sport. I love manuals and a good project. Not in a hurry to get this done and would wait for local deals on parts/existing breakage. I could not find much on the fx37/qx70 platform. I’ve read a ton on G/Z swaps and what little forum posts are around for the fx35.

References:
A Comprehensive Guide to 6MT Swapping a G37 - MyG37
3.7L - Has anyone put 3.692 axle into a RWD?
FX35 - Manual Trans Swap

Electrical:

ECU: Confirmed with Uprev that the manual toggle is preset in qx70 roms. They advised I disable all transmission codes. The QX70 never came in manual.

TCU: Pigtails for starter and reverse tapped from original TCM harness (F51 "A/T Assembly"). This seems to be the same plug described in post 7 of the linked G37 thread


AWD: I’d have to go RWD. I’ve seen people switch the controller ground to deactivate the awd system. I could live with the dashlight if it can't be tuned out. Will a ground switch work long term?

Cruise control clutch switch wired in parallel with brake cruise switch.

Any other modules to consider? Think this let me keep the adaptive cruise functions?

Interior:

Handbrake, pedals, Master/slave, shifter cutout, lines, etc. are well documented on g37 forum. I’m confident I can adapt a manual center console to look good enough.

Drivetrain:

G/Z trans

G/Z rear diff (3.692) with axle flanges

Rear Axles:
Option 1: I found these adapters(FDF Raceshop - 350Z/370Z to Quick Change Axle Adaptor) Could I have a similar "adapter" made to mate stock QX70 axles to G37 flanges?

Option 2: I found this process for a 240-350 axles (240SX to 350Z Axle Adapters!). Largely custom but seemingly less involved than option 3.

Option 3: I read in a forum that the QX and G axle diameter is the same. If true, could I mount the inner CV (diagram part 2) from G/Z axles on the longer QX axles? This would allow them to bolt to the diff flanges from the G/Z. I can't find any pictures of the QX CV internals to confirm they're compatible with the G/Z


Front Axles: deleted. Will I need rwd hubs? Rwd BCM to remove the awd controller?

Driveshaft: G37 + spacers? I've seen spacers mentioned several times but never actually pictured. Would this just be similar to a wheel spacer? Is a full custom driveshaft the only viable route?

I appreciate your insight

 

[LA_DRIVER]

For the rear diff the only differences I've found btw our cars and the g37 diffs are the thickness of the flanges on the stub axles. The CV axle flange could be thicker as well, but possibly not. Definitely confirm I've seen with my own eyes the stub axle comparison. This could be where the excess length is created btw the two models. The FX37 AWD models came with the 3.692 gear ratio, so look for a used one of those as it will be cheaper than a g37 diff carrier. Part #38301-EG50D

For the driveshaft ours measures 64 3/8" tip to face. I had Inland Empire Driveline make me one for around 1k. One-piece aluminum with foam. No increase in NVH. Hope this helps! Good luck!

 

[mnz4]

Appreciate this info and good note on the FX diff!

For the rear diff, is it just flange thickness? I was also under the impression the hole pattern was larger on the FX/qx. Can you clarify?

From what I've gathered I'll need an extra inch on the driveshaft to compensate for the shorter trans. Your measurements are a good starting place

 

[LA_DRIVER]

I actually have an FX diff that I took apart (mostly) and can send you pics of the stub axles and/or diff carrier. Lets chat via DM. I'm not using some of the parts and could part with them if you need.