4.11 VTD tranny swap video

[NeedForSpeed]

Originally Posted by Nevin

Turns out it DID fix it. Imagine that, running the right parts will make it do what it should. Crazy idea, right?

http://www.youtube.com/watch?v=d27_QwlZk2Q

Haha

When I asked what your TCU specs were, you realized you hadn't installed the SVX TCU ?

Any binding now?

[Nevin]

Originally Posted by NeedForSpeed

Haha

When I asked what your TCU specs were, you realized you hadn't installed the SVX TCU ?

Any binding now?

Yeah, the TCU just has the ECUtune shift program and the stock SVX shift points. I didn't really see the need to raise the shift points at all. And yes, putting in the wrong tcu = bonehead move.

Yes, there is a bit of binding still, but it only does it when I turn very short. I have worked on other LSD's before that have done this for a bit until broken in. Plus it did sit in my garage for 2 years, so I wonder if that had anything to do with it. But no binding at all when I'm taking off in D or R or at any speed when driving and no jerky movements or funny noises, only when I'm turning very sharply.

[Nevin]

For what it's worth, I keep hearing less and less popping, and the speedo reads just about dead-on when compared to my friend's GPS.

Put a bunch more miles on the car today, and keep smiling when doing so!

And this thing is even more beastly in snow now. I'm also running 205/55r16 snow tires, but it's nearly unstoppable. Goes through a foot of the white stuff with ease.

[Nevin]

Well I have some news. Not necessarily good or bad news yet, but news.

I decided to take the car drag racing today as is a january 1st tradition at the local (80 miles away) drag strip known as Hangoverfest! The news is that about 35 miles into the trip, we were about ready to get on interstate and I heard a funny whir-ish kinda grindy sound. Didn't sound good at all. The car put itself into 3rd gear so I slowed down, and there was a gas station to pull in to, so I did and as I came to a stop in a parking space there was a horrible screeching sound and some general bad sounding grinding noises. Now when I put it in reverse it does nothing, and when I put it in drive it makes horrible sounds.

So, the car came home on a flatbed (thank you, girlfriend's AAA) and I'll take a look at it this week if I can. I'm not in an enormous hurry or anything as it's not my daily, but if anyone has any suggestions, I would love to hear them. I guess I'll know for sure once I get it apart.

[NeedForSpeed]

Well, I haven't been paying attention, or checking in enough, since my mid-December birthday, on through the holidays. Sadly, it looks like I'm catching up too late. I'm sorry to read your last post, I don't believe the news is good .

Continued popping could be a sign to park the car, not continue to drive it, not to put more miles on it, not to race it. There is never any harm in collecting advice and testing changes with the necessary goal of eliminating the binding, whether the concern is a center diff or rear diff. In hindsight, a bit more caution could have been used, especially since VTD is a major mod and the SVX was not your daily driver. It won't break in the garage. The first VTD trans we built, about four years ago, a 4.444, had binding, and was parked for two years trying to sort it out. The noise sounds like rear diff, but isn't.

In re-reading your posts, it appears that previous experience made you assume that the noise was the rear diffential, not stress or noise in the center differential? In assuming so, were you doing figure-8s, thinking to 'free-up' a rear diff? You said the noise was lessening, was this lessening occuring while mainly driving in a straight line, carefully avoiding sharp turns which you said resulted in more noise, or were you sharp-turning and circling with the goal of lessening the noise?

There are many posts on the Euro forum discussing binding problems [noise, popping] in the center differential with VTD transmissions. YT had some posts about his 3.545 VTD binding issues in the car he sold. I believe that he first tried a stock JDM SVX TCU, or was that a ECUTUNE JDM SVX TCU?

Noise in the center differential can be from one of two causes. First cause, solonoid C is stuck or not functioning properly. This has happened to several VTDs worldwide, a problem once considered improbable. I've had binding in a newly installed US transmission, and thought it must be the newly built matching rear diff, even swapped rear diffs, only to find out it was the solonoid. Swapping the solonoid fixed it. Admittedly, there is confusion when installing a new-to-the-car transmission and rear differential.

The second cause of VTD binding is improper TCU programming. You said ECUTUNE would program the TCU for your 4.111 VTD, starting with a stock JDM TCU. A stock JDM SVX VTD TCU will not properly operate a JDM 4.111VTD transmission, thus, the need for TCU programming. Re-reading your reply on Christmas Day, that the TCU "just has the ECUtune shift program" leads me to believe that the SVX TCU wasn't programmed to run your transmission combination as I had assumed.

In reading your last post, I would believe that the center differential has self-destructed. Likely, the teeth of the planetary gears have sheered off. If that is truly what happened, the cause of destruction is continued driving with binding. To my knowledge, no one has continued to drive a binding VTD car, so, nothing is known about consequences.

Again, the cause of any binding is either a bad solonoid-C, or a TCU that was not properly programmed for transmission spec. I would think that driving on snow or ice would be more forgiving in either cause, if in fact, the center differential was effectively 'diff-locked' due to one of the above.

[longassname]

Hey Ron,

I know you had Phil locate the constant for the gear ratio for you but you guys seem to be the only ones that know it. I thought I made that clear when I said it would be nice if you guys shared it.

I'm not doing anything in secret. I went public quite a while ago with everything I had and have been publishing any TCU modifications I make in Phil's thread along with the data locations in the different years and regions so that anybody can do anything I'm doing without having to come to me to get it done.

I guess Nevin will have to come to you to run 4.11 gears.

[Nevin]

Ron, I only put about 60 miles on the car with the VTD, and it only popped when I would turn very hard. Honestly, I just tried avoiding sharp turns after that. No figure 8's for me. I had assumed (incorrectly I suppose) that IF the ratios were different I would have heard a much more prominent popping sound and a general feeling of binding even just driving in a straight line. As to whether or not it's sol. C, I'll just have to investigate and find out.

And I'm not worried about the TCU being wrong. Michael and I were very clear with eachother as to what the TCU would be running in, so I don't believe that is the issue.

And I have no problem with something being my fault and me fixing it. Heck, that's how you learn right? I have every confidence that the trans will eventually go back in the car and work properly. But, for now the stock trans will go back in, and that's just fine with me.


On a sidenote, Michael, would I be able to use the valve body from the JDM trans in the US trans? I really liked the quick shifts, and if I can use it in the stock SVX trans, I would really like to in the meantime while the other trans is diagnosed.

[longassname]

Nevin,

I don't know much/anything about the vtd parts but assuming that is what failed I wouldn't take the transmission out. All that would be in the extension housing which can be removed with the transmission still in the car. You might want to open it up and take a look--maybe even take some pictures so we can see what's in there and clarify what needs replacing.

On the US cars people don't seem to have any problem with the TCU not being set for the correct gear ratio but that may not be the case with the vtd transmissions. I really don't know anything about them so I couldn't tell you but I'd look into it. Maybe you can get Phil to correct it on your TCU. The ROM I gave you is a 27sf512 which is rewriteable.

[Nevin]

Originally Posted by longassname

Nevin,

I don't know much/anything about the vtd parts but assuming that is what failed I wouldn't take the transmission out. All that would be in the extension housing which can be removed with the transmission still in the car. You might want to open it up and take a look--maybe even take some pictures so we can see what's in there and clarify what needs replacing.

Since I won't be able to get the parts on short notice (I'm assuming here) I think I'd prefer to just pull the trans and put the stocker back in then figure out the problem. I'm not a huge fan of downtime, espescially since it'll be sitting at work. Besides, it only takes like 6 hours to do a tranny swap anyway.