Reference thread: https://ls1tech.com/forums/gears-axl...ange-koni.html

After chasing some vibrations, I learned Strange basically developed the wrong transmission slip yoke for their driveshafts for T56 transmissions. They have been using the yoke U1662 for nodular iron, or U1667 for chromoly. I spoke directly to Strange and they admitted they found a fault in the design of both of these yokes when used with a T56 transmission. Basically, the inside of the splines do not fit tight enough to the output shaft of the transmission, causing vibrations. They concluded that their new U1662F or U1667F yokes are redesigned about 5 months ago to be tighter and stronger, and made SOLELY for use with a T56 transmission. They also said anyone who has moved to this new yoke has reported vibration-free operation, and none have been reported broken yet.

I received the new U1662F yoke yesterday and compared it to my old U1662. First off, the yoke is about 3/8" longer (don't quote me, I didn't get an exact measurement, just a guess), and the yoke is stamped with SPICER and a part number C3-3-649-2. The old yoke had no brand indicators and looked lower quality. I measure the inside diameter across the inside of the splines to be around 1.177" on the old yoke, and around 1.168" on the new yoke. The new yoke still slides onto the output shaft very smoothly, even with the tighter I.D."

When I took out the old yoke, I noticed I already had twisted splines, and this driveshaft has only been in my car a little over a year of daily driving, and highway pulls, and ONE day at the drag strip with about 6 passes no higher than 3000rpm on drag radials. I know a lot of people report twisting splines on Strange yokes with high horsepower cars on slicks, but I didn't think it was possible for my car to do so.

My conclusion is these new yokes should be much stronger than the old design for 3 reasons: 1) tighter spline engagement, 2) longer yoke to engage the output shaft more and 3) SPICER!... After a test drive, my car had significantly reduced vibrations, so there's another bonus. I'm sure we will see far fewer twisted Strange yokes with this new design!

I regret I was in too much of a hurry to snap some comparison pics, but take my word on this.

The newly revised cast yoke U1662F was about $79, and the newly revised chromoly yoke U1667F is about $179. These parts are not yet listed in their catalog, so you have to call to order.

 

Nice talking with ya at the hobby shop, hope it all irons out for ya

 

Got a picture of my stock OLD yoke that only had ONE DAY with about 6 track passes on it. My passes were on 315/35/18 Toyo Proxes TQ drag radials, with a Monster Stage 2 clutch, and never over 3000 rpms, and my lowest 60' was 2.01' (Need a lot more practice, first time at the strip in this car). Let's see how well the new yoke holds up.


Thanks man. Sorry I didn't get to chat long, I was trying to get this done ASAP. I know I've seen the red SS around, and now I see it's got a D1 eh? I'm planning a F1A myself within the next couple of years.

 

Glad I was able to help and even more glad you got it figured out! Congrats

Zack

 

Thats a hella lot of twist for 2.0 60's..... Spicer forged here 1.6x on high dumps and et street dr's for years, no issues so far.

 

I agree. This one is stamped SPICER on it, so let's hope it holds up a bit longer. I don't see the drag strip but one weekend a year, because they are too far away, so I'm not too concerned about this one. But when I step up to some slicks, I'll probably just opt for a Mark Williams yoke.

 

Wise plan. Spicer great and all but MW> Spicer if and when needed.

 

Excuse me when I say, that is fu**ing bullshit on their part. They manufactured a faulty part, then sold it to people. Realized they fucked up, and then want to charge their customers again for the part they should have had in the first place?

I've had this issue since day 1 as well when I bought a new yoke around 15 months ago. Glad to know what the issue is now, but damn is that frustrating.

 

Yeah its tricky to stay on top of who is actually selling the "good stuff" or just pimpin crap off a good name. Its always going on to some degree or another. I for one cant fathom the short sightedness of it all? Why would anyone want to trash a good brand with cheap substitutes is beyond me but so many cant seem to see beyond this quarter *sigh*

Caveat emptor so be careful, and do your homework before laying out your green

 

I agree it's BS. I've read about two other people sending in their driveshaft and they replace the yoke for no charge and shipping included. I did not want to do that, and instead just wanted a new yoke. I really tried to get them to pay for it, but I paid Midwest Chassis to spec the Strange shaft, and was told I had to take care of it through MWC. They weren't familiar with the issue at all at that point, and nobody offered to pay for it. Oh well, I needed it quickly, so I didn't feel like fighting it.

 

Sorry to dig up this old thread but the mark williams inner diameter (minor diameter) between the splines is 1.101" and they sell the same part number 39005 for use on both a T56 in the F-body and the 4L60E with no change between the two.

So if 1.101" is going to fit a 4L60E and not be too tight, why would a strange U1667F with a 1.168" ID not work with the 4L60E, and be SOLEY used with the T56?

While the old design of the strange U1667 was not a tight enough fit, is it safe to say that their newer design U1667F works just fine on a 4L60E?

Page 21 lists 2 options for spicer 1350 that is 27 spline. (2 different plugs, one my have a weep hole, the other not, but they both have the same major ID of 1.218"

http://media.spicerparts.com/cfs/fil...store=original