GTM Valve Body Upgrade Review

timp · 03-04-2013, 12:52 AM

I wanted to share my thoughts on the install of the GTM Valve Body upgrade for the 7AT transmission and invite comments on others who have installed the GTM VB as well.

1) As everyone knows the 7AT has had some issues with slow or lazy shifting from one gear to the next, hunting for the right gear when down or up shifting or having to mash the gas pedal to get the transmission to down shift when passing. In order to correct these issues many have resorted to getting the ECU re-flashed (I have tried this as well) with minimal results.

2) When wanting to go FI, unless something is done to firm up the shifting in an automatic transmission to prevent slipping and keeping the trans oil from overheating the auto transmission can be a ticking time bomb. Case in point: in 1998 I purchased a brand new 1999 F350 Super Duty Ford pickup with the V10. I also installed a brand new Paxton SC from Banks Engineering along with long tube headers. The SC plus the headers added about 200 HP. The transmission lasted 4 months. $7500 dollars later I had a built proof transmission that could bark the 36” tires in second gear. The truck serviced me for 13 years no problem until it was stolen. The point is that according to the repair shop that rebuilt the transmission they said that if I would have installed a shift kit and a heavy duty transmission cooler right away likely the transmission would not have had to be rebuilt. Lesson learned!

What to do for all the G37/370Z owners wanting to change the attitude of their 7AT and add some insurance to the longevity of their transmission? Get a GTM Valve Body upgrade and transmission cooler.

I contacted Sam at GTM and expressed my concerns about the 7AT and installing the twin SC kit. Sam suggested installing the reworked valve body first before installing the SC kit. Sam emailed the down load link for the re and re manual and I set to work on removing the valve body. The step by step instructions provided were very precise down to the pictures and warnings / cautions / suggestions. If you have a metric socket set, assorted screw drivers, wrench set and minimal automotive know how anyone could do this valve body re & re. I did the work myself and it was so easy. Mind you I have a hoist in my shop so that made thing much easier.

Just follow the detailed instructions, drain the oil in a clean 2 gal bucket and remove the oil pan. The instructions tell you what bolts to undo to remove the valve body and the instructions even show the different lengths of the various bolts and where they go. Unplug 2 sets of wires and you are done. About a 2 hour job.

20121123_073518.jpg

Follow the instructions for shipping and handling and send it off to GTM. GTM received my valve body at 2 pm on a Monday and it was ready to ship back to me the next day by 4 pm! Valve body was re-installed Friday.

20121130_101512.jpg 20121130_095528.jpg

Buy a new pan gasket cost is about $40. To refill fill the transmission first calculate how much oil came out plus a few quarts extra. Buy a $13.00 hand pump from any automotive store. You will need to fabricate a fitting to screw into the refill port on the bottom of the oil pan opposite the drain plug. I did this at a cost of $12.

20121207_143630.jpg

Follow the directions from the GTM manual for refilling the transmission and you are done. Sam will send you a re-flash file to upload to your ECM and your car is ready to go.

As an alternative you could contact your Infiniti/Nissan shop and they could do the re & re for you. I was quoted $250. Maybe a good time to get your transmission oil flushed and changed at the same time.

Driving the car after the valve body upgrade is so much more fun. It is like driving a different car. In standard D mode going easy on the throttle you can feel the up shifting firm but not too much. You don’t want the transmission banging into gear all the time only when you need it. Stand on the throttle and get ready for some fast and firm shifting. Put the car into DS or manual mode and it feels just like a standard only a lot faster up and down and with no missed shifts.

Another thing I noticed is when driving is DS mode and you do some fast deceleration hard on the brake pedal the transmission rev matches and downshifts so much better than before. Same thing when in DS mode and wanting to pass another car or when you want to accelerate out of a corner you don’t have to mash the pedal so hard and over rev the engine. The transmission downshifts faster and with authority. D = mode great driving. DS / M = fantastic driving.

In conclusion the car feels and drives like a sports car should. In my opinion of all the mods a person can do to the Infiniti G37/Nissan 307Z (whether going FI or not) doing the VB upgrade is right on top.

GUTCH · 03-04-2013, 02:14 AM

Thanks for the write-up.

Can the upgrade only be done by GTM or can they send the parts out and we have our own installer do it?

blueranger · 03-05-2013, 12:12 AM

Nice review.. Thanks for taking the time

GUTCH · 03-09-2013, 06:59 AM

Quote:

Originally Posted by GUTCH

Thanks for the write-up.

Can the upgrade only be done by GTM or can they send the parts out and we have our own installer do it?

Anyone?

diddy535 · 03-09-2013, 08:45 AM

Any value to a 6MT?

Nixlimited · 03-09-2013, 10:24 AM

Quote:

Originally Posted by diddy535

Any value to a 6MT?

No. There is not the same hardware in a 6MT.

Mike@GTM · 03-11-2013, 01:30 PM

Tim,

Thanks for posting up your review!

Quote:

Originally Posted by GUTCH

Thanks for the write-up.

Can the upgrade only be done by GTM or can they send the parts out and we have our own installer do it?

This is an in-house service only. For overseas customers looking to have minimal downtime, you can purchase a brand new valve body from us that we modify and send out. Then, all you do is swap valve bodies once you receive the new valve body from us.

GUTCH · 03-12-2013, 03:12 AM

Quote:

Originally Posted by Mike@GTM

Tim,

Thanks for posting up your review!

This is an in-house service only. For overseas customers looking to have minimal downtime, you can purchase a brand new valve body from us that we modify and send out. Then, all you do is swap valve bodies once you receive the new valve body from us.

Thanks!

Eighties Meta · 03-12-2013, 08:57 AM

hmmn, I really hate driving mine around in D and this seems like it may be the ticket. Especially in heavy traffic between 20-30mph it's clunky and annoying, and having to floor it to get it to downshift is annoying also which is why I drive in DS most of the time. Unless this is outrageously priced I'm liking the prospect of doing this

future370zzz · 03-13-2013, 01:20 AM

Subbed

GUTCH · 03-13-2013, 02:33 AM

Would the GTM Racelogic traction control upgrade be a worthwhile modification to work in unison with the vavle body upgrade?

Jordo! · 03-13-2013, 02:41 AM

Nice review

Z eliminator · 03-13-2013, 08:42 AM

i have the built 7 AT with the race logic.
i have not had the race logic running with the 7 AT yet.
will post when i install it.

wstar · 03-13-2013, 09:24 AM

Is the core charge fully refundable if we do the "swap and send back the original after" option? Also, for HPDE / TT / Road-racey stuff (I'm probably one of the few doing that on a 7AT), does GTM have a recommended set of upgrades for the 7AT on an NA motor? The VB upgrade is on my list, do any of the other bits you sell make sense as well? Basically my power hasn't increased much, I just need the thing to be a bit more bullet-proof under track abuse and firmer/faster shifts would be nice. Mine's used almost exclusively in M-mode.

Mike@GTM · 03-13-2013, 02:14 PM

Quote:

Originally Posted by wstar

Is the core charge fully refundable if we do the "swap and send back the original after" option? Also, for HPDE / TT / Road-racey stuff (I'm probably one of the few doing that on a 7AT), does GTM have a recommended set of upgrades for the 7AT on an NA motor? The VB upgrade is on my list, do any of the other bits you sell make sense as well? Basically my power hasn't increased much, I just need the thing to be a bit more bullet-proof under track abuse and firmer/faster shifts would be nice. Mine's used almost exclusively in M-mode.

The valve body on the 370Z has a TCM that is coded specifically for the VIN that it is installed on. This renders the valve body useless to any other VIN. There are two ways around that: 1) the dealer can reflash the TCM and code it for the vehicle it is installed on. 2) a brand new valve body can be ordered directly from Nissan and coded for the VIN directly from the factory.

Therefore, for all practical purposes, there is no exchange program. That said, we are working on a solution but it is very capital intensive and not on the top of our priority list at the moment.

For a track car, there are two items I would recommend in addition to the valve body upgrade. First, if you don't already have one, is a transmission cooler. Second, a transmission fluid temperature gauge. Monitoring transmission fluid temperatures is extremely important if you are tracking the car. In fact, I would recommend a gauge with a Peak/Warn feature so you don't have to stare at the gauge while bending corners.

Basically, the reason a gauge is so important is that as transmission fluid temps increase, the life of the fluid decreases dramatically. Here is an article I wrote that goes into a little more depth: http://www.gtmotorsports.com/Technic...ansmission.pdf

While that is specific to forced induction with automatics, it has some good information that does apply to what you are doing with your car.

03-04-2013, 12:52 AM	#1 (permalink)
timp Base Member Join Date: Jan 2012 Location: British Columbia Posts: 3 Drives: 09 Infiniti G37X 2DR Rep Power: 13	GTM Valve Body Upgrade Review I wanted to share my thoughts on the install of the GTM Valve Body upgrade for the 7AT transmission and invite comments on others who have installed the GTM VB as well. 1) As everyone knows the 7AT has had some issues with slow or lazy shifting from one gear to the next, hunting for the right gear when down or up shifting or having to mash the gas pedal to get the transmission to down shift when passing. In order to correct these issues many have resorted to getting the ECU re-flashed (I have tried this as well) with minimal results. 2) When wanting to go FI, unless something is done to firm up the shifting in an automatic transmission to prevent slipping and keeping the trans oil from overheating the auto transmission can be a ticking time bomb. Case in point: in 1998 I purchased a brand new 1999 F350 Super Duty Ford pickup with the V10. I also installed a brand new Paxton SC from Banks Engineering along with long tube headers. The SC plus the headers added about 200 HP. The transmission lasted 4 months. $7500 dollars later I had a built proof transmission that could bark the 36” tires in second gear. The truck serviced me for 13 years no problem until it was stolen. The point is that according to the repair shop that rebuilt the transmission they said that if I would have installed a shift kit and a heavy duty transmission cooler right away likely the transmission would not have had to be rebuilt. Lesson learned! What to do for all the G37/370Z owners wanting to change the attitude of their 7AT and add some insurance to the longevity of their transmission? Get a GTM Valve Body upgrade and transmission cooler. I contacted Sam at GTM and expressed my concerns about the 7AT and installing the twin SC kit. Sam suggested installing the reworked valve body first before installing the SC kit. Sam emailed the down load link for the re and re manual and I set to work on removing the valve body. The step by step instructions provided were very precise down to the pictures and warnings / cautions / suggestions. If you have a metric socket set, assorted screw drivers, wrench set and minimal automotive know how anyone could do this valve body re & re. I did the work myself and it was so easy. Mind you I have a hoist in my shop so that made thing much easier. Just follow the detailed instructions, drain the oil in a clean 2 gal bucket and remove the oil pan. The instructions tell you what bolts to undo to remove the valve body and the instructions even show the different lengths of the various bolts and where they go. Unplug 2 sets of wires and you are done. About a 2 hour job. 20121123_073518.jpg Follow the instructions for shipping and handling and send it off to GTM. GTM received my valve body at 2 pm on a Monday and it was ready to ship back to me the next day by 4 pm! Valve body was re-installed Friday. 20121130_101512.jpg 20121130_095528.jpg Buy a new pan gasket cost is about $40. To refill fill the transmission first calculate how much oil came out plus a few quarts extra. Buy a $13.00 hand pump from any automotive store. You will need to fabricate a fitting to screw into the refill port on the bottom of the oil pan opposite the drain plug. I did this at a cost of $12. 20121207_143630.jpg Follow the directions from the GTM manual for refilling the transmission and you are done. Sam will send you a re-flash file to upload to your ECM and your car is ready to go. As an alternative you could contact your Infiniti/Nissan shop and they could do the re & re for you. I was quoted $250. Maybe a good time to get your transmission oil flushed and changed at the same time. Driving the car after the valve body upgrade is so much more fun. It is like driving a different car. In standard D mode going easy on the throttle you can feel the up shifting firm but not too much. You don’t want the transmission banging into gear all the time only when you need it. Stand on the throttle and get ready for some fast and firm shifting. Put the car into DS or manual mode and it feels just like a standard only a lot faster up and down and with no missed shifts. Another thing I noticed is when driving is DS mode and you do some fast deceleration hard on the brake pedal the transmission rev matches and downshifts so much better than before. Same thing when in DS mode and wanting to pass another car or when you want to accelerate out of a corner you don’t have to mash the pedal so hard and over rev the engine. The transmission downshifts faster and with authority. D = mode great driving. DS / M = fantastic driving. In conclusion the car feels and drives like a sports car should. In my opinion of all the mods a person can do to the Infiniti G37/Nissan 307Z (whether going FI or not) doing the VB upgrade is right on top. Legz, Jordo! and CarbonSignal like this.

03-09-2013, 08:45 AM	#5 (permalink)
diddy535 Track Member Join Date: Feb 2012 Location: St. Louis, MO Posts: 789 Drives: '09 370Z RAE 6MT Rep Power: 14	Any value to a 6MT? __________________ ( Click to show/hide ) http://www.the370z.com/members-370z-...ys-thread.html

03-12-2013, 08:57 AM	#9 (permalink)
Eighties Meta Enthusiast Member Join Date: Aug 2012 Location: Pasadena, MD Age: 54 Posts: 344 Drives: 09 370z 7AT no-sport Rep Power: 13	hmmn, I really hate driving mine around in D and this seems like it may be the ticket. Especially in heavy traffic between 20-30mph it's clunky and annoying, and having to floor it to get it to downshift is annoying also which is why I drive in DS most of the time. Unless this is outrageously priced I'm liking the prospect of doing this __________________ 2009 370z Touring 7AT/AAM 2.5 true dual exhaust/AAM DE test pipes/z1 vqde35 headers/AAM cold air intake (R-line)/Motordyne M370/Quaife LSD/z1 brake upgd pkg/Swift Spec-R springs/WhiteLine Front&Rear sway bars with endlinks

03-13-2013, 01:20 AM	#10 (permalink)
future370zzz Track Member Join Date: Dec 2011 Location: Bay Area Posts: 555 Drives: 10 Nissan 370z Rep Power: 14	Subbed __________________

03-13-2013, 02:41 AM	#12 (permalink)
Jordo! A True Z Fanatic Join Date: May 2010 Location: nirvana Posts: 6,394 Drives: 2023 NATM Rep Power: 418	Nice review __________________ Enjoy it. Destroy it.

03-04-2013, 02:14 AM	#2 (permalink)
GUTCH Base Member Join Date: Jun 2010 Location: Australia Posts: 134 Drives: 2018 Audi TT RS Rep Power: 15	Thanks for the write-up. Can the upgrade only be done by GTM or can they send the parts out and we have our own installer do it?

03-05-2013, 12:12 AM	#3 (permalink)
blueranger Track Member Join Date: Aug 2012 Location: Albuquerque NM Posts: 577 Drives: 2010 Roadster 7AT Rep Power: 307	Nice review.. Thanks for taking the time

03-13-2013, 02:33 AM	#11 (permalink)
GUTCH Base Member Join Date: Jun 2010 Location: Australia Posts: 134 Drives: 2018 Audi TT RS Rep Power: 15	Would the GTM Racelogic traction control upgrade be a worthwhile modification to work in unison with the vavle body upgrade?

03-13-2013, 08:42 AM	#13 (permalink)
Z eliminator A True Z Fanatic Join Date: Jul 2009 Location: Ontario Canada Posts: 1,659 Drives: 370 Z 7AT Sports Rep Power: 19	i have the built 7 AT with the race logic. i have not had the race logic running with the 7 AT yet. will post when i install it. __________________ 12.343 @114.14 . 4.5 stroker motor is now being built. Dec 1 2015.

03-13-2013, 09:24 AM	#14 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	Is the core charge fully refundable if we do the "swap and send back the original after" option? Also, for HPDE / TT / Road-racey stuff (I'm probably one of the few doing that on a 7AT), does GTM have a recommended set of upgrades for the 7AT on an NA motor? The VB upgrade is on my list, do any of the other bits you sell make sense as well? Basically my power hasn't increased much, I just need the thing to be a bit more bullet-proof under track abuse and firmer/faster shifts would be nice. Mine's used almost exclusively in M-mode. __________________ 7AT Track Car! Journal thread / Car setup details

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