Transmission not centered in tunnel

[16GoManGoHC2]

While installing new DSS DS noticed Transmission is not centered in the tunnel. M6, 825 wheel, Anyone ever see this before? Motor and or tranny mounts shifted?? Suggestions?

When removing stock DS noticed Barton shifter mounting leg is touching side of opening on drivers side

 

[SilverBillet]

You may need to talk to Barton about that? Hopefully you don’t have to modify the tunnel? There is no problem if the transmission cross member and transmission mount are bolted up. They can’t be shifted or bolted up wrong. The engine crankshaft centerline is offset from the body centerline. The trans input shaft, driveshaft and rear pinion have to line up with the engine centerline. I don’t know the specs but the rear differential is not centered either and I believe the right and left axles are going to be different lengths to accommodate the offset centerline of the drivetrain. That’s also how the classic Mopar’s with solid rear axles were made. I assume it’s still like that?

 

[BULL]

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[16GoManGoHC2]

Going to take it out tonight for a shake down pull and see if it rubs.
The Barton in the cutout is only touching ever so slightly, I’ll have to watch tonight and see which way, left or right the shifter moves under hard acceleration

 

[coolblue]

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I know in the old days when they had U-joints on the ends, the pinion and tranny were NOT supposed to line up, and yes the solid axle rears had different lengths. But is that how Mopar does it now? When I was looking at the 4" driveshafts on G-force website (not DSS)they did have a disclaimer that it may hit and have to be clearanced. But I thought that was a disclaimer and maybe the exhaust, but is this what they were talking about?

 

[16GoManGoHC2]

Only issue I’ve read is clearance to the exhaust system and shifter, I have no issue around either to DS just DS to passenger side of tunnel.

 

[oilburner]

my a8 is the same, I`m sure its normal. very noticeable when installing one piece shaft.

 

[steven_sbs]

Is it possible the transmission is centered in the chassis, but the tunnel is not centered in the chassis making it look like the transmission is not centered? Could the tunnel be asymmetrical giving more clearance on one side for shift linkage, foot space inside the cabin, or something else?

 

[oilburner]

Is it possible the transmission is centered in the chassis, but the tunnel is not centered in the chassis making it look like the transmission is not centered? Could the tunnel be asymmetrical giving more clearance on one side for shift linkage, foot space inside the cabin, or something else?

I`m sure the engineers had their reasons.

 

[16GoManGoHC2]

When installing Barton shifter before mods for more HP I don’t remember it being so close to one side of the cutout like it is now, of course this was a look from the top side not underneath but one would think engineers would center things in cutouts and tunnels???

I’ll be testing it later today to see which way the shifter kicks when stomped on, if it twists towards the drivers side that would only make it hit even more, if twist is toward passenger seat then ok I guess then. Either way I’ll be lifting it up afterwards to look at DS
I’ll post findings

 

[MiHiHemi]

That's exactly why guys are getting vibration when changing to a one piece drive shaft. FCA went with a two piece shaft for a reason.

 

[coolblue]

That's exactly why guys are getting vibration when changing to a one piece drive shaft. FCA went with a two piece shaft for a reason.

I tend to agree with you on this but I don't know why. What?? Meaning, yes I agree they def did it for a reason but don't know why. The old early/mid sixties Chevy Impalas did this but those cars were HUGE. The Challenger(albeit bigger than Camaro/Mustang) is just NOT that big, so why? I read an in depth article on this a ways back but don't know where or I would post it. I believe it said something to the fact that X amount of horsepower driven through a shaft at X amount of angle could take X amount of twisting/abuse. And when you put it through a shorter shaft at even a little more angle it could take more HP. So the Germans (basically the Challenger is based on the 300 series platform) engineered it so that two shorter shafts could take more HP and upset the chassis less with 2 shorter shafts rather than one long one for better handling.
Hey Mike it's after 8:00PM. You take that thing out for a shakedown yet?

 

[16GoManGoHC2]

Yes, took it out and up to speed, can feel it at 75-80 and again at 140. Weird Can’t feel it in the shifter but can feel it in the seat of your pants. It’s not terrible but it’s not as smooth as the stock shaft. Haven’t had a chance to look under it though, my back is killing me, putting up the exhaust system alone yesterday put me backwards in the healing process. Hopefully be lifting it up tomorrow and see if it rubbed any where and index the rear yoke 180 degrees and spool it up again. BTW the shifter moves slightly towards the passenger side under load, good for shifter leg rub but not good clearance wise DS to tunnel. We’ll check it out and advise, hopefully get to do a run afterwards but most likely will be dark by then and be Thursday before next test run.
Stay tuned lol

 

[coolblue]

Yes, took it out and up to speed, can feel it at 75-80 and again at 140. Weird Can’t feel it in the shifter but can feel it in the seat of your pants. It’s not terrible but it’s not as smooth as the stock shaft. Haven’t had a chance to look under it though, my back is killing me, putting up the exhaust system alone yesterday put me backwards in the healing process. Hopefully be lifting it up tomorrow and see if it rubbed any where and index the rear yoke 180 degrees and spool it up again. BTW the shifter moves slightly towards the passenger side under load, good for shifter leg rub but not good clearance wise DS to tunnel. We’ll check it out and advise, hopefully get to do a run afterwards but most likely will be dark by then and be Thursday before next test run.
Stay tuned lol

Edited my earlier reply. See if that makes any sense to you. Take it easy and feel better.

 

[16GoManGoHC2]

Yes, I understand the engineering behind 2 pc shafts with a center support. I looked at a upgraded 2 pc unit but their pricey, figured I’d give a DSS a whirl first.

 

[Confuzed1]

my a8 is the same, I`m sure its normal. very noticeable when installing one piece shaft.

I tend to agree it's normal. Even the drivetrain in my old '83 Camaro is offset a little towards the passenger side. I always understood (and may have been told) that it's designed that way to have the clearance needed for steering shaft and box. Makes me wonder if right hand drive cars are offset the opposite of ours......

 

[Deebeezie]

Swapped out my DS for my CCI this past weekend in my ‘18 Charger and noticed the same thing. Ensured there was no rub and then took it out for the shake down. No issues, and more importantly, zero vibration at speed.

 

[Magnified]

Now that is interesting. Is this the same in the Charger? Looks like it would be easy to tell from the parts (half-shafts being left or right side ONLY). I don't recall noticing this type of the offset in the Charger when I have it up, but that doesn't mean i didn't miss it.

 

[Deebeezie]

I did certainly notice the offset on my Charger.

 

[16GoManGoHC2]

Lifted and checked for rubbing this evening, all clean. Indexed the DS 180 at the diff flange, will see tomorrow is any smoother, would have tonight but my kids car is in front of the garage door and he went out with friends and no spare key around, needless to say he got a happy txt lol