I installed my GTM Aluminum Driveshaft yesterday and encountered a problem.

The GTM driveshaft is significantly wider than the OEM one. There's a weight welded at the end of the GTM driveshaft that sits directly under the shifter/selector when installed and the amount of clearance between the shift linkage and driveshaft is only about 5mm! So during the test drive, the driveshaft snagged the dust cover and ripped it completely off and is now missing leaving the linkage exposed. All the grease from the shifter is dripping onto the driveshaft from the heat and it's turning black.

I ordered a new dust cover from Nissan but I'm confident it won't fit and will just get ripped off again during the driveshaft's first rotation.

Has anyone with an aftermarket driveshaft experienced this problem? Any ideas how to fix this problem quickly?

Edit for photos: Photos are blurred due to insufficient space and light. Clearance between driveshaft/weight and shift linkage is ~2-5mm depending on which gear you're in and if you're measuring from the weight or driveshaft wall. Clearance looks exaggerated due to close-up shots.

I also forgot to mention the increased vibration through the shifter and cabin. I just re-checked the 4 bolts connecting the driveshaft to the rear differential and they're all tight. Flanges are flush. I can see the shift **** vibrate quite a bit and the cabin vibration feels like a shimmy from an imbalance wheel.

 

I have no suggestions. Auto or Manual?

Coop

 

Manual. I need to find a fix quick because we have thunderstorms and rain in the forecast. This is my DD. I might look for some sort of elastic, fireproof cap to temporarily protect it from the elements.

 

Updated with photos.

 

Quick fix would be stock driveshaft back in until u get that figured out. Damn!

 

Might have to do this if I can't figure it out by tomorrow. I rarely get days off from work and I'm usually too tired to work on the car when I get home from a 10 hour shift.

Might be a long shot but there was a small piece of rubber from the dust cover hanging on the shift lever as shown at the top of the first picture. Maybe this caused the shifter to vibrate as the driveshaft spun and the weight hitting it. Honestly the shifter vibration was more violent than a small piece of rubber could cause but you never know. As for the shimmy, I'm going to re-torque my wheels and spacers to rule out those possibilities.

 

Welding that counterbalance weight at that position = incorrect.

ANY shimmy is an out of balance condition. New driveshaft + correct mounting + shimmy/vibration + clearance issues = return.

GTM is not the manufacturer. Although they jobbed this out.

I'd like to be wrong, but the manufacturer ought to redo this one. Good luck.

(I'm on an OEM driveshaft because I anticipated potential problems on my setup.)

Coop

 

It suprises me that GTM failed to catch this. I knew the driveshaft would be slightly larger in diameter than the OEM but this seemed unusually large at first sight.

I'm going to remove this in the next couple of hours and put the OEM back in. I'm expecting to have to send it back. I'm glad I only had to wait a month for this and spend extra money tryng to fix it and replace torn parts from it.

Is it too late to get in on the CF GB?

 

What did GTM have to say about it? They obviously had to have installed it and put the covers back on?

 

GTM did not install his driveshaft he did it himself..i would send it back and put the OEM back on

 

Correct. I installed it with the help of a friend and without running into any issues along the way. It's a simple, straight forward install (re-aligning my E370 was way more difficult!).

I just finished removing the GTM driveshaft and re-installed the OEM. A little more difficult without help and laying on my back in a dim and dirty underground garage but as before, the swap went flawlessly.

I'm waiting to hear back from GTM about this issue and what their protocol will be. I sent pictures and an explanation of the problems I had with it. I'll report back with updates once I hear from them.

 

I just got off the phone with Sam from GTM. I'll be sending the driveshaft back to GTM to be inspected and rebalanced after the weight is relocated. Sam mentioned they sold a good handfull of these driveshafts and this is the first time they've ran across this issue.

I'll report back once I hear from them again after inspection.

 

Sounds like you may have just been unlucky. Good luck buddy. I hope that you get it sorted.

 

We received the driveshaft and checked the balance. It was balanced correctly before we did anything with it. It looks like the short throw shifter sits lower under the car than the factory shifter and was rubbing on the balance weight, causing vibration. We moved the weight forward on the driveshaft to give additional clearance and rebalanced the shaft. The aluminum driveshaft we offer is a 4" diameter shaft and so far, this is the first time there has been any issue with clearance.

As for the shift boot, you may consider using safety wire to hold it up higher against the chassis. We suspect that it may have ripped off when you pushed the shifter down to engage the reverse lockout. There's a ton of room between the shift boot itself and the shift linkage, so take advantage of that room and pull it up higher.

Sam

 

Thanks for chiming in, Sam!

First off, let me start by saying Sam and GTM have been very helpful from day 1. They stand by their products, workmanship, and will do whatever it takes to make problems right. Top notch guys at GTM.

Now...I received the driveshaft back from GTM yesterday and installed it immediately. Installation went perfectly and I also replaced the rubber shift boot that was ripped off with another OEM one. $20 and an easy fix.

Once the driveshaft was in I took the car out for a test drive and immediately noticed increased NVH from the shifter like the first time I installed the driveshaft. I've had the TWM short shifter installed for a while now and never felt it vibrate like this. It's a strong, high frequency vibration and it transfers throughout my right arm, especially at WOT and I almost have to let off the gas or let go of the shift **** to relieve the jarring sensation. It's noticeable at all points throughout the entire RPM band and even while cruising. It seems strongest at ~50MPH from what I remember. When I put the OEM driveshaft back in, the NVH was gone and back to normal.

Nothing else has changed on my car other than the driveshaft. I double checked that all the bolts were tight and the counter weight wasn't hitting the shift linkage. I thought maybe there was something causing this before that was masked by the OEM driveshaft - is that possible?

Any ideas where this extra shifter NVH is coming from and how to fix it?

Oh, and the rubber shift boot is still in tact! I'll be moving it higher once I get back under the car next week.