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If you've been a member of this forum for a while, specifically within the C5 community, and your into modifying your car there's no doubt that you've looked into shifter modifications. The stock system has excessive play in each mechanical interface from the shift lever all the way through the internals of the transmission. There are quite a few products out there to replace the shift lever mechanism itself as well as the box and bushings that it interfaces with. I replaced the whole unit with once made by MGW and love it, however for those of you obsessed with a perfect driving feel that wont be enough. The next week link in the system is the linkage between the shift box and the transmission itself. This linkage consists of connections at either end, which are actually surprisingly free of any play, as well as 2 u joints to prevent binding. These u joints have a ton of play, or slop by design. They are block and pin style joints meaning that in order to function there much be some play in the fitment. All well and good in some applications, not in this one in my opinion. I believe nsogiba pioneered a fix to this issue, but many followed his lead soon after including tastybacon and myself, which consists of cutting out the old U joints and replacing them with bearing style steering U joints. This project is fairly simple as fabrications goes, but if you dont have access to a welder or other necessary fabrication tools then it is then impossible to fix this problem. Recently Tusc asked if I'd be able to do that job for him after striking out as local fabrication shops. Tusc builds some pretty impressive cars and there was no way i was going to let him leave the sloppy U joints in such a high quality build, so i took on his project. In most DIY cases guys have used the torque tube transmission shifter set up as a jig in order to ensure proper fitment. In this case I had to make my own jig, luckily I have access to a machine shop to do so. Below I will post a picture of mine assembled on the torque tube as well as a before and after picture of the one i just finished up for Tusc. I will add a stem by step of my process to this thread soon. Disclaimer: I am not a professional fabricator or mechanic but i di take pride in my work. Feel free to check out my build thread here for my recent vette project as a reference.https://www.corvetteforum.com/forums...e-rebuild.html
Front u joint before mod Rear u joint before mod mid fabrication mod complete
Glad you know what you are doing. I really didn't even know what kind of joints were down there, never even looked into it beyond thinking the shifting could be better. So, making a decision about the design function , good or bad , is beyond me. that does look like it is a nice part, and the C5 shifting could stand some work, just check all the posts on the subject.
But I can add to this discussion, from reading over in the general topics auto crossing and performance section, where there are tips in the top header , the permanent post area, where the writer was discussing race car prep.
He also wound up with the MGW shifter, and briefly discussed how it took some getting used to.
He also suggested , as another solution that still had the familiar feel with improved function, which he ran before the MGW shifter, was to bolt in a C7 shifter from the Z model, much improved and a perfect bolt in, according to him. The guys backs up his cred with a picture of his nice crashed C5, but the post is so old that not all of the included links I tried in the story worked.
That is, if I remember the info correctly. It was kind of dense, he also disdained the paragraph.
I just figured I would add that in, since the info pertains to this common problem, and probably not too many people go to that area or plow through that post,
When I investigated the remaining slop in my linkage after having done a custom rework of the factory shift box, I found that the major source of slop is in the transmission itself - and in my case it is very much oriented to the low gears, the 1-2 plane; hardly any at all in the 3-4 or 5-6 planes.
When I investigated the remaining slop in my linkage after having done a custom rework of the factory shift box, I found that the major source of slop is in the transmission itself - and in my case it is very much oriented to the low gears, the 1-2 plane; hardly any at all in the 3-4 or 5-6 planes.
Interesting that you would point that out jackthelad. I've got that answer to that one too. Over the winter I rebuilt my trans noticing 1-2 had excessive slop compared to higher gears, I had figured it was just me or that they were extra warn do to the frequent used and quick abusive 1-2 shifts. However, this is again inherent to the design of the transmission. Take a look at the picture i'll post below. The way that your trans shifts is by rotating that pin in between 1 of 4 forks, or linkages. Whatever you want to call them. Theres 3 in the picture, missing the 1-2 linkage. However the 1-2 and 3-4 linkages are identical. The interesting thing is that the clearance between that pin and the 1-2, and 3-4, fork is about 0.060 where the clearance between the pin and both the 5-6 and R forks is only about 0.020. Therefor 1-4 is inherently sloppier feeling than 5, 6 and R. If your thinking that 0.040 difference doesn't sound like a lot then consider it would equate to at-least 1/8 inch of play in the shift **** with a short throw shifter, more with a standard shifter. Then add in the more abusive shifts on 1-2 and the cracking that are inherent to the shift pads and thats the problem your experiencing. I both machined my own brass fork pads that were a good snug fit, press on the fork and 0.001 slip on the synchro and then i added weld and re-machined the 1-2 and 3-4 brackets to have the same 0.020 slip that the other 3 gears had. What a difference that made. I initially though id be replacing my second gear synchro when i tore into it and after all that there was no need to.
original linkage re-machined linkage new fork pads
I bent my shifter linkage during a clutch install about 1/8" shorter. 1st/3rd would pop out of gear when trying to accelerate. Needed to slot the mounting holes in my MGW shifter about 1/8" more to compensate.
When I eventually replace it I'd like to mod it with better u joints.
Last edited by smitty2919; Jul 9, 2020 at 03:55 PM.
Hey guys, pulling this thread back from the dead because i have some new information that i thought would be worth sharing. I'm building another one of these modified linkages for C5Z06CE and this time around I'm starting with a brand new linkage. What was interesting to me is the lack of slop in the brand new linkage. I found about 0.005 0f play per side, 0.010 total slop, which in the shift handle would equate to about 0.050 of slop due to this issue alone, Thats not all that bad considering that the one i built above on this thread measured in at over 0.040 total slop, close to 1/8 inch at the shift ****. either way this mod with will then have effectively 0 will be an improvement. but thats a lot of wear in joints that don't flex all that much.
Either way, C5Z06CE, this is going to be a big improvement over what over the current worn linkage. Thanks for bringing me in on the build of such an impressive C5.
If anyone has any questions about this mod, i'm about to start work on this one and can post any details that you need to be able to complete your own.
Here is another way to reduce slop. I went to lathe shop and the guy who works there machined new "centers" for the stock joints.
My stock cross-pins had a lot of play in old "centers", but now they were pressed in into new centers - so there is no more slop at all. And they still can rotate in U-shaped ends. Also, lubrication is a must. Old stock centers on the table, new one already in joint
Here is another way to reduce slop. I went to lathe shop and the guy who works there machined new "centers" for the stock joints.
My stock cross-pins had a lot of play in old "centers", but now they were pressed in into new centers - so there is no more slop at all. And they still can rotate in U-shaped ends. Old stock centers on the table, new one already in joint
That's a big improvement. What was the cost?? Have you hit the road yet for real world feel??
It was about 30$. Have not driven it yet, there are tons of snow here in Russia.
I only ran through the gears on the table - looks very tight and precise for me, like a rifle. But it wasn't really that bad before the mod as you may think, it just reduces side-by-side play.
It was about 30$. Have not driven it yet, there are tons of snow here in Russia.
I only ran through the gears on the table - looks very tight and precise for me, like a rifle. But it wasn't really that bad before the mod as you may think, it just reduces side-by-side play.
And i thought you guys put slides under your tires on the front of your cars.
Great idea bobick. Looks to have achieved a very similar result with less headache. It’s true that the linkages are typically functional as is but you’ll be much more satisfied with the shift feel I’m sure.
Shift Linkage U Joint Mod
