Seriously: 4AT to 6MT swap

[digitalbow]

NissanClub,

Update: The engine and transmission are in, but I have not addressed the manual transmission mount. It will be welded to the frame, or bolted-through sometime this week.

Background: I am working through an engine replacement (my original VQ35 burned a lot of oil at rapid pace), while also replacing the transmission because the automatic began to fail. Taking advantage of this opportunity, I am converting to a 6-speed manual with LSD. The purpose of the swap is to handle the 400+ ft-lbs of torque better than the 4AT RE4F04B - which, although offers a better gearing advantage for the turbo setup, is incapable of withstanding the power and heat.The tear-down in March '09 by pulling the old VQ and transmission and with very sporadic work over, the new motor and transmission are now in. The donor vehicle is for the transmission is a 2002 Maxima. The motor is new. Note that not all of the parts from the Maxima are a direct swap. Approximately 45 man-hours have been invested so far, including; removal of the old engine and transmission, bolting-in the new motor and transmission, and some interior work projects.

My parts list:

• RS6F51H 6-speed transmission w/ helical limited-slip differential
  - MT brake pedal (from a 3rd-gen Altima)
  - MT half-shafts (from a 5MT or 6MT Altima, or 5th or 6th-gen Maxima, depending on ABS or TCS)
  - Clutch fluid reservoir and line, master cylinder, clutch pedal (from a 3rd-gen Altima)
  - Stainless braided direct clutch line (much easier instead of using the hard lines)
  - Transmission mount (from a 5.5-gen MT Maxima, or 3rd-gen MT Altima)
  - Shifter assembly, linkages, knob, boot, and bezel (need the Altima SE-R shifter assembly, MT Altima linkages, and a reverse-lift compatible knob)
• VQ35DE FWD long block (2005)
• '03 Altima SE ECU (manual trans ECU)
• '02 Altima SE information cluster panel (manual trans)
• Fidanza flywheel
• Exedy clutch kit

Some difficulties and delays encountered thus far:

• As mentioned above, some items from the donor vehicle are different; the transmission mount, shifter assembly and bezel, half shafts, and shifter cables. Source Altima parts specifically for these to save some worry about compatibility. The other major parts are interchangeable, though.
• I had a small rust line to take care of along the floor of the passenger-side, along the door.
• I really don't have the time for this project...

Apparently we have only one 3rd gen on the forum who has converted from AT to MT (altima02dub - but with a 2.5) and a few who have experimented with converting 5MT to 6MT and adding the hLSD. I could use some wisdom and help from you all as I move along.

There are still a few concerns that I haven't resolved yet, so if anyone has some ideas, please let me know:

• There are two wire differences out of the ECM for the MT - the PNP switch and the ASCD signal. I haven't progressed to the point to figure these out yet, but I don't think it will be a big deal.
• I'm not sure if I should remove the TCU harness and box or leave it.
• I haven't figured out the wiring for the reverse gear signal yet.

I'll be documenting as much as I can for you guys in this thread as I move along, so please keep extraneous comments to a minimum.

Thanks in advance.


At this point, here is what is left to do:

• Put in new axle seals and attach the half shafts, fill the trans with oil, attach the speedometer pinion, and weld the MT mount to the frame
• figure the wiring to fool the reverse signal, PnP and ASCD to cooperate with the ECU
• install new oil pan and drain line
• reinstall the intake manifold, turbo down/up pipes, and O2 sensors
• finish up the interior odds and ends, and connect all remaining sensors

Some pictures to document the process:


RIP old VQ: Lucky to have a few buddies help me lift out the 530lb paperweight (busted VQ and transmission)




Pulling the AT crap out:



MT vs AT shifter



Maxima 6-speed parts in the box:




New VQ35DE:




Fidanza Flywheel



AT and MT ECUs

[digitalbow]

A few more pictures of some odds and ends:


A closeup of that stupid metal piece that sticks out underneath (I unbolted mine - it is listed as an 'air guide' for the A/T - shown in the mounting diagram below)



The rust I was talking about earlier? Yeah, check yours out. I fixed mine with a few minutes on the die grinder and then some primer, however other members have cautioned that it may extend further. This is a big thing to check on your Altima, as this appears to be VERY common. Fix it before it becomes a bigger issue, trust me.




Maxima shifter cables



Multitasking...



Putting the new VQ in was actually the easiest part so far...



Exedy clutch



Fidanza flywheel installed


NGK Iridium IX - These are one step colder than stock range

[digitalbow]

6sp Altima SE-R red stitch shift knob - not by any means a 'weighted' knob, as it measured at a whopping 135 grams, but feels nicer than the 5.5-gen Maxima knob.



SE-R shifter assembly and knob installed



The dreaded AT mount bracket, which is welded to the frame. - You will see in later pictures that I cut it off.



The MT mount, which bolts through the rail in the same location where the bracket (above) was welded.



I confirmed all of the differences by viewing the following diagrams on CourtesyParts:

AT mount diagram


MT mount diagram (same for all 02-06, 5MT and 6MT VQs)

[digitalbow]

A few other odds and ends:

2002 M/T shift console/boot - This '02 faux wood grain one was $40 cheaper than the ones that most of you replace with. I think the overall design was updated in 2003 so that the boot could be removed/separated from the actual console - this one is not removable.



6sp Altima SE-R speedometer pinion - The AT pinion is blue, but has the same dimensions as this one. You may not need to replace it.



MT and AT information clusters - You only need this to mitigate the shift indicator light panel, which is no longer used.



MT cluster and custom gauge pod installed - I'll get you guys more info on the pod once I get everything running. It looks 10x better in person.



6MT and starter, bolted up - Note that the transmission mount is not attached yet.



The engine and transmission, in the engine bay - The easiest way to do this (if you do not have access to a real lift, or do not want to drop the subframe) is to bolt the engine to the 6MT outside of the car and then wedge it in together.

[digitalbow]

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[digitalbow]

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