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  #21 (permalink)  
Old 05-26-2019, 08:51 AM
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Originally Posted by CJ428CJ View Post
You don't really have any other options do you unless you want to change the rear end gear ratio. Presumably you have 2.88 or maybe 3.07 gears. If you go with a Tremec 600 you might be able to get away with 3.07 gears but I think 3.31 or even 3.54 gears are much preferred.
Now that you mention rear end gear ratio, my Cobra has 3.50 gears in it already. While the combination of RG with 1:1 5th and 3.50 rear gears is not ideal for highway driving, it works great around town which is about 95% of what my Cobra gets used for these days. So replacing the RG with an OD trans makes even more sense to bring the highway RPMs down and resolve all the RG trans issues I have and surely will have with continued use.

All things being equal, buying a new OD trans (most likely a Tremec) and swapping out the RG makes the most sense. But I'm 95% done with a replica Ferrari 250 GTO that I intend to start using as my around town driver. So my incentive for big ticket upgrades on the Cobra is low. I guess having both these cars is a good problem to have but it's hard not wanting to have all my cars to be perfectly optimized and have no issues.

I sent you a PM with contact info since we live near one another. Would be great to meet another Cobra guy in the Tri Valley area.
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  #22 (permalink)  
Old 05-26-2019, 09:52 AM
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Joel I don't think trans is locked in 2 gears at the same time. As soon as you would get it in 2 gears the tires would lock up or it would strip the gears out of the trans. This would happen even with the clutch pushed in. When this happens does your tires slide?
Something is going on but I am not sure of what.
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  #23 (permalink)  
Old 05-26-2019, 01:44 PM
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Originally Posted by MAStuart View Post
Joel I don't think trans is locked in 2 gears at the same time. As soon as you would get it in 2 gears the tires would lock up or it would strip the gears out of the trans. This would happen even with the clutch pushed in. When this happens does your tires slide?
Something is going on but I am not sure of what.
Exactly. If it ever selects / engages two gears at once something will have to give . One possible cause is failure of the weld on the individual shifter shaft/arm where it pass's thru the side of the case, I struck this once, it causes/allows the interlock to be 'out of phase' and leaves the trans in the previous gear when you shift up or down.
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  #24 (permalink)  
Old 05-26-2019, 06:57 PM
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Originally Posted by MAStuart View Post
Joel I don't think trans is locked in 2 gears at the same time. As soon as you would get it in 2 gears the tires would lock up or it would strip the gears out of the trans. This would happen even with the clutch pushed in. When this happens does your tires slide?
Something is going on but I am not sure of what.
Generally, any manual transmission would be trash if two gears were selected at the same time. While one gear stays selected, it would take effort to select the other gear.

Clearly, it cannot be gears that share the same hub, like 1/2 or 3/4 in this case.

Gary
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  #25 (permalink)  
Old 05-27-2019, 09:16 AM
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Originally Posted by Gaz64 View Post
Generally, any manual transmission would be trash if two gears were selected at the same time. While one gear stays selected, it would take effort to select the other gear.

Clearly, it cannot be gears that share the same hub, like 1/2 or 3/4 in this case.

Gary
Great points guys. I don't know exactly what it is when the trans gets into this state. It happened to me again yesterday when I had the Cobra out for a drive around town. I happens for 2nd to 3rd shift only.

Here's what I do know. When shifting from 2nd to 3rd (issue happens when RPMs over 3,500 almost never below that), the shifter handle feels like it seizes up in mid-motion and won't let you select any gear but reverse which doesn't engage but gives a big grind noise. If I let the clutch out when trans is in this state, the rear tires squeal like they are locked up. I don't know if the drive train is really locked up or if the trans is really just still in 2nd gear. I have always kept the clutch depressed because I don't want to break something and the only fix I've found for the issue is to shift into reverse. The shift into reverse can only happen when the car is at a full stop. Once at a full stop and shifted into reverse, the trans is now cleared of the state and can be shifted normally into any other gear.

I guess the next time the issue happens, I can let the clutch out once the car slows down some and determine if in 2nd gear or not. If the trans is really in 2nd gear and shifter is not in 2nd gear position, that would tell me it's a really a shifter issue and not a trans issue. Oh well, doing more diagnosis gives me an excuse for more spirited driving! "Really officer, that wasn't an exhibition of speed, I was just trying to diagnose an issue with the transmission."
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  #26 (permalink)  
Old 05-27-2019, 12:30 PM
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I have the exact same rear gear 2:88. I have the richmond 4+1 5 speed transmission with a 1-1 fith gear and it is Perfect for freeway driving. I am going by memory here but i think at 70mph im doing about 2500 rpm
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  #27 (permalink)  
Old 05-28-2019, 04:46 PM
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Originally Posted by C5GTO View Post
Great points guys. I don't know exactly what it is when the trans gets into this state. It happened to me again yesterday when I had the Cobra out for a drive around town. I happens for 2nd to 3rd shift only.

Here's what I do know. When shifting from 2nd to 3rd (issue happens when RPMs over 3,500 almost never below that), the shifter handle feels like it seizes up in mid-motion and won't let you select any gear but reverse which doesn't engage but gives a big grind noise. If I let the clutch out when trans is in this state, the rear tires squeal like they are locked up. I don't know if the drive train is really locked up or if the trans is really just still in 2nd gear. I have always kept the clutch depressed because I don't want to break something and the only fix I've found for the issue is to shift into reverse. The shift into reverse can only happen when the car is at a full stop. Once at a full stop and shifted into reverse, the trans is now cleared of the state and can be shifted normally into any other gear.

I guess the next time the issue happens, I can let the clutch out once the car slows down some and determine if in 2nd gear or not. If the trans is really in 2nd gear and shifter is not in 2nd gear position, that would tell me it's a really a shifter issue and not a trans issue. Oh well, doing more diagnosis gives me an excuse for more spirited driving! "Really officer, that wasn't an exhibition of speed, I was just trying to diagnose an issue with the transmission."
Maybe the brass synchro's are seizing up on the "cone" part of the gears, blocking the slider sleeve from fully engaging the selected gear. Maybe try a different lubricant ? Synthetic gear lube ?
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  #28 (permalink)  
Old 05-30-2019, 08:54 AM
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Maybe the brass synchro's are seizing up on the "cone" part of the gears, blocking the slider sleeve from fully engaging the selected gear. Maybe try a different lubricant ? Synthetic gear lube ?
Thanks for the suggestion. I really don't think it's a failed syncro issue as the trans shifts just fine between 2nd to 3rd gear all the rest of the time. I do have a quality, synthetic gear lube in the trans. I tried to reproduce the issue yesterday with some "spirited driving". No luck, like most intermittent issues, it doesn't manifest itself when you want it to. Oh well, more spirited driving another day.
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  #29 (permalink)  
Old 05-31-2019, 02:41 PM
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well, i know david kee doesn't recommend synthetic for toploaders, as the tranny sometimes doesn't shift right, i.e. block shifts due to synchro issues. He recommends standard gear lube. I know the richmond is the really the doug nash 5 spd, which was at least in the past "old" technology, like the toploader.

call richmond. maybe they can guide you.
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  #30 (permalink)  
Old 06-05-2019, 08:21 AM
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Default RG shift issue diagnosed - it's a shifter issue

Ok, while driving yesterday the RG "stuck shift" occurred again. Like the times before, on the shift from 2nd to 3rd gear at about 4,500 rpms, the shifter felt like it seized up and wouldn't allow me to select any gear. This time I allowed the car to slow to about 20 mph and I released the clutch. The trans was still in 2nd gear, it could be driven that way but could not be shifted to another gear until the car was brought to a full stop and reverse gear engaged.

So from this, I deduce that I have a "shifter" issue and thus not a transmission issue per se. The shifter is a Hurst Competition Plus that was bought new when I built the car in mid-90s and now has close to 50K of mileage on it. The car has had this shift issue for a couple of decades now so it started occurring prior to the shifter having much wear on it. The issue occurs a lot more frequently now so it has increased as the shifter has been used more.

Has anyone else had a similar issue with a Hurst shifter and experience fixing it? If so, I'd appreciate any tips you may have. I of course could replace the shifter but I wouldn't mind to give it a try to fix it just for the experience.
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  #31 (permalink)  
Old 06-05-2019, 01:03 PM
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Ok, while driving yesterday the RG "stuck shift" occurred again. Like the times before, on the shift from 2nd to 3rd gear at about 4,500 rpms, the shifter felt like it seized up and wouldn't allow me to select any gear. This time I allowed the car to slow to about 20 mph and I released the clutch. The trans was still in 2nd gear, it could be driven that way but could not be shifted to another gear until the car was brought to a full stop and reverse gear engaged.

So from this, I deduce that I have a "shifter" issue and thus not a transmission issue per se. The shifter is a Hurst Competition Plus that was bought new when I built the car in mid-90s and now has close to 50K of mileage on it. The car has had this shift issue for a couple of decades now so it started occurring prior to the shifter having much wear on it. The issue occurs a lot more frequently now so it has increased as the shifter has been used more.

Has anyone else had a similar issue with a Hurst shifter and experience fixing it? If so, I'd appreciate any tips you may have. I of course could replace the shifter but I wouldn't mind to give it a try to fix it just for the experience.
Does your shifter have steel or nylon bushings? Mine had the latter, and when they wear the shifter gets sloppy. Replace the bushings in the shifter and make sure it's adjusted properly. Use the Hurst Pit Pack with steel bushings. https://www.summitracing.com/int/par...7302/overview/
https://www.shifterdoc.com/productca...ngs-53p336.htm

Hurst owners's manual / instructions: https://www.shifterdoc.com/4070009_Install.PDF
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Last edited by cycleguy55; 06-05-2019 at 01:07 PM..
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  #32 (permalink)  
Old 06-05-2019, 01:19 PM
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well, i know david kee doesn't recommend synthetic for toploaders, as the tranny sometimes doesn't shift right, i.e. block shifts due to synchro issues. He recommends standard gear lube. I know the richmond is the really the doug nash 5 spd, which was at least in the past "old" technology, like the toploader.

call richmond. maybe they can guide you.
RG recommends GL4 / GL-4 for those transmissions - particularly their own 80W90. It's petroleum lube, not synthetic. https://www.richmondgear.com/auto-pa...smission-faqs/

At one time there was a note you could use a particular Redline synthetic gear lube, but that's what I have in mine right now and it made the shifting worse - particularly 4-5 where I can easily beat the synchronizer.

Edit: Found it! "What oil should I use in Richmond manual transmissions? Richmond T-Lube, high performance synthetic manual transmission fluid. Richmond T-Lube is designed for extreme load and long duration exposure in high performance manual transmissions. Richmond T-lube is designed to withstand high heat and provide anti-score protection for high speeds. Red Line 70/90 NS is also acceptable." https://www.richmondgear.com/wp-cont...g_Section2.pdf
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Old 06-05-2019, 02:35 PM
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Does your shifter have steel or nylon bushings? Mine had the latter, and when they wear the shifter gets sloppy. Replace the bushings in the shifter and make sure it's adjusted properly. Use the Hurst Pit Pack with steel bushings. https://www.summitracing.com/int/par...7302/overview/
https://www.shifterdoc.com/productca...ngs-53p336.htm

Hurst owners's manual / instructions: https://www.shifterdoc.com/4070009_Install.PDF
Yes. Seems consistent with an alignment issue, either the shifter rods may need to be adjusted , or maybe there's an issue internally with the tranny, with the selector plates/detentes.
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Old 06-05-2019, 05:02 PM
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Joel I have a new unused hurst shift tower. I started to take it apart to see what makes it tick. I need to clean the parts up in the parts washer . Old dried up grease. It has been 20-25 years since I have taken one of these apart. I also need to find the box with my mustang Hurst shifter in it. I made a hybread shifter with some of the parts for my RG 5 speed. OK if I remember right a 4 speed hurst it is spring loaded to one side. The Hurst RG shifter is spring loaded to the3-4 gate. When I get it cleaned up I will see if I can figure out how you and mine shifter is doing what it is doing. Might take a couple of days. You got me wondering!
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Old 06-05-2019, 05:28 PM
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Ok I found my old Hurst 4 speed shifter. I guess I just cut the weld to get the non removable shifter stick off of the mustang shifter. I welded it on the RG shift tower so the shifter could be used with my console. I also make a new mounting plate to lower it
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Old 06-05-2019, 05:49 PM
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Joel how are you shifting when this happens? Are you just doing a normal shift at 4500. Or is some type of a speed shift? I just don't know why engine RPM has anything to do with it. When it happens to me I am shifting at 6500 and not lifting on the gas. I am only pushing the clutch far enough to disengage and as fast as possible.
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Old 06-06-2019, 08:22 AM
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Joel how are you shifting when this happens? Are you just doing a normal shift at 4500. Or is some type of a speed shift? I just don't know why engine RPM has anything to do with it. When it happens to me I am shifting at 6500 and not lifting on the gas. I am only pushing the clutch far enough to disengage and as fast as possible.
It's just a normal shift from 2nd to 3rd. I let up on the gas and fully depress the clutch. The only thing different is the higher rpm.

I'm guessing the higher rpms make it so more pressure is needed to move the internal shift ring to disengage 2nd gear. My theory in this case is the internal shift ring doesn't make it all the way off 2nd gear before the Hurst shifter plunger is disengaged from the associated 1st/2nd shift plate. The shifter plunger has now engaged in the 3rd/4th shift plate but the RG internal cams/plungers are doing their job in preventing 2nd and 3rd gears to be engaged at same time.

I'm guessing at lower rpms and thus my theory is less pressure, the internal shift ring goes into neutral for that gear set with much less persuasion from the external shifter. Maybe it's poor tolerances in the Hurst shifter, could be some wear in addition to that, or maybe an adjustment issue. I'm hoping for the last of these possibilities but I've adjusted the shifter several times and it's always had this issue. I'm anxious to hear about if you can pinpoint the root cause in your case. Please keep me updated.
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