So, about a month ago, I decided to swap out the original T-10 transmission on my Carryover over to a brand new World-Class T-5 Tremec. The belief was that having the extra gear would allow for easier highway driving. I made the swap and even posted about how pleased I was with the ability to run 70 MPH at 2,200 RPM - I was in heaven!
However, I started to realize that the transmission would grind each time I went into 5th gear, and 5th gear only. I could down shift from 5th to 4th with no issues, and there was no grinding if I double clutched going into 5th (which I later learned eliminated the 5th gear synchro).
I called TREMEC, and after running several tests at my home, they decided I needed to send the original transmission back for warranty repair. I pleaded with them to replace the transmission, but they refused. In the end, I had the transmission removed and shipped back to TREMEC. TREMEC then did the warranty repair and sent the transmission back for installation.
The reinstallation was just completed, and for the first 5-8 shifts from 4th to 5th, there was no grinding. However, now the transmission, once again, grinds every time I shift from 4th to 5th. Ugh!
I'll call TREMEC this morning, as I'm guessing they changed the 5th gear synchro (and maybe 5th gear). However, it seems that the 5th gear synchro is the symptom, not the problem. Something is causing the 5th gear syncro to go bad.
Thoughts?
Shifter malfunctioning?
Clutch fully disengaging?
Quote from: 2112 on October 02, 2019, 10:00:22 AM
Shifter malfunctioning?
Clutch fully disengaging?
Good questions. We checked the clutch several times, and it is fully disengaging (this was one of the first tests TREMEC had me preform the first time). I hadn't thought about the shifter, though.
Ruben, was it MDL suggesting calling Tremec? Could be a bad batch of sychros. My friend who rebuilds the 2000e gearboxes used in English Fords deals with this
all the time. It's really hit or miss.
Quote from: gjz30075 on October 02, 2019, 10:45:28 AM
Ruben, was it MDL suggesting calling Tremec? Could be a bad batch of sychros. My friend who rebuilds the 2000e gearboxes used in English Fords deals with this
all the time. It's really hit or miss.
Hey Greg - thanks for the info! Yes, it was MDL that suggested calling Tremec. And, I fear you may be correct, regarding the synchros, as that seems to be the weak link...pun intended. ;)
Quote from: Shelby_r_b on October 02, 2019, 10:06:47 AM
We checked the clutch several times, and it is fully disengaging (this was one of the first tests TREMEC had me preform the first time).
Out of curiosity, and in an attempt to assist, please expound on the procedure executed?
Also, perhaps your typical technique of engaging 5th leading to the difficulty?
Realize that attempting to discover the solution on a forum from afar is not really likely, but perhaps, some food for thought may be conjured. And , you asked. :)
Scott.
Please don't read my post about T10 issues recently, I almost teared up reading your post. I had nightmares, rebuilt trans was a mess. Best of luck with your issue. Peter
Did they provide trans fluid with the transmission? Or recommendations? I have a fairly new T5z in one of my cars, and I get an occasional grind going into third. I have been experimenting with different fluids. I have a semi-synthetic in now. I was thinking about trying the GM Syncromesh people seem to rave about.
I'm not sure if it should have a non synthetic in it at first as a break in oil. The car wasn't assembled when I bought it, but I don't think the trans had been used at all.
Quote from: Shelby_r_b on October 02, 2019, 11:18:32 AM
Yes, it was MDL that suggested calling Tremec.
And, thank you for your order!.............N E X T !!!! :o
Scott.
Engine too strong for the transmission? I've read that it isn't necessarily the best to put a T5 with a hipo 289 or Boss 302 combination. But if that's the case I would think you'd have a lot more than that problem.
Quote from: deathsled on October 02, 2019, 12:37:56 PM
Engine too strong for the transmission? I've read that it isn't necessarily the best to put a T5 with a hipo 289 or Boss 302 combination. But if that's the case I would think you'd have a lot more than that problem.
+1 :-\
My 66 GT350 loves the T5, No issues at all.
T5z is rated for 330 ft-lbs
Ruben, what fluid is in it? Synchros are very sensitive to the type fluid used. Sometimes, too slippery is not the way to go. Here's a thread that may be of interest discussing the preferred fill of 50W vs. ATF vs. 75W/90 gear oil.
https://www.allfordmustangs.com/forums/5-0l-tech/320994-what-best-fluid-t5-transmission.html
Thanks to all! A couple of quick answer before proceeding:
- The clutch does completely disengage, as this has been verified through 2 different tests. Plus, if the issue were the clutch (according to Tremec) the grinding would happening in other gears or coming out of 5th to 4th
- I don't recall off hand which oil was used. The first time the tranny was installed (prior to issues), I used the fluid provided by MDL. The second time the tranny was installed, I used fluid sent straight from Tremec with the rebuilt tranny - they were both different brands, but I couldn't tell you what type
- MDL wanted to help; however, Tremec's policy is to have their warranty work completed by their technicians (or, at least that's what Tremec said)
- The T-5 is (from what I understand) not a bad transmission for a HiPo 289; however, it all depends on how the car is driven and if the engine has many power modifications. Tracking with this tranny is no bueno - it's better to step up to the TKO 5-speed from what I understand.
I just got off the phone with Tremec, and they are going to do a 1 for 1 swap. I asked what they thought was causing the problem, and they said it could be two items that, if out of tolerance, would take out the 5th gear synchro. Also, they confirmed that they changed the 5th gear synchro and 5th gear originally before sending the transmission back. Also, another person had the same issue with their T-5 (although the serial numbers were very far apart), and their components are being sent to Mexico for testing as well.
So, I'll drive it for now, double clutch it into 5th, and wait for the new tranny to come. The saga continues! ::)
Quote from: pmustang on October 02, 2019, 12:10:28 PM
Please don't read my post about T10 issues recently, I almost teared up reading your post. I had nightmares, rebuilt trans was a mess. Best of luck with your issue. Peter
I hear you, Pete! I did read your thread recently...it sent shivers down my spine. I hope you're getting things sorted out in the end. :'(
Hmmm... I considered following in your footsteps on this swap, but now my T-10 is looking like a keeper. Can't wait to see how this sorts out. Certainly seems like a lot of trouble for a brand new trans. Who's paying the shipping & multiple installation bills?
Steve
Redline MTL seems to be a magical formula for fixing issues like this. Try it.
I think though what you have run into is the traditional problem of over driven gears with "high powered" vehicles. Simply put, don't do it. Traditionally, the over driven gear can't handle it.
Not to sell anyone a "Doug Nash 4+1", i.e., a Richmond 5 speed, but originally the most significant criteria justifying building it was/is that 5th gear is 1:1, not over driven. The weakness of overdrives has been known as an engineering issue seemingly forever.
Anything based off of a T5 is going to have patchwork engineering fixes to a weak design.
Your T5 needs another repair and likely will continue to fail in 5th. It's just a bad design. It was intended to run behind a 210hp 302. That's all.
I would take an educated "engineering guess" here and say that if the transmission is rated for 330lbs-ft of torque, take whatever the overdrive number is, .68? Multiply that time 330 and that's really what 5th gear can hold? That number comes out to 224.5. That's what I think that trannie can hold in 5th.
BS to the manufacturer. They lied.
Lots of overdriven Tremec transmissions behind 662+ HP modern Mustangs without failing.
Those supercharged engines come on like a freight train. Popular modifications bring quite a few up to 800 HP at the rear wheel.
Of course, those aren't T-5's
I have used t-5 transmissions behind 400 HP small blocks with no problems. A couple of very important things to consider is that there are a couple of t5 model trans made. One was for the 4 and 6 cylinder cars and then they made a beefier version for the higher HP cars. You need the beefier version or there will be problems. Also if you do not use ATF in at least the earlier version of the t5 you will have shifting issues. MDL is your friend here they are very knowledgeable with all things t5.
Some guys can break anything. Some guys are numb nuts. Maybe it's the same thing?
Personally I've snapped two shift LEVERS off of transmissions. As Eddy Murphy once said, "gooney-goo-who Gus?" The Hurst people thought it was funny but wouldn't cover it.
Kopec always wanted me to be "FE Wedge". I declined the appointment.
When it's broken i want to know why. If it wasn't me, then it's the component. Hey? Why's everyone looking at me and shaking their heads? That's not fair. :o
I had never heard of a shift lever snapping until about a month ago. My 16 year old did it on his 96 Cobra. My 14 year old welded it up for him an he's been driving it ever since.
I would never recommend a T5 for a track car or drag car, but it is great for cruising. Fifth gear will never see 330 foot pounds of torque on the street, unless you're really flying.
Quote from: pbf777 on October 02, 2019, 11:52:35 AM
Quote from: Shelby_r_b on October 02, 2019, 10:06:47 AM
We checked the clutch several times, and it is fully disengaging (this was one of the first tests TREMEC had me preform the first time).
Out of curiosity, and in an attempt to assist, please expound on the procedure executed?
Also, perhaps your typical technique of engaging 5th leading to the difficulty?
Realize that attempting to discover the solution on a forum from afar is not really likely, but perhaps, some food for thought may be conjured. And , you asked. :)
Sorry for backing up in the post, and my intentions are not to badger, but, generally in order to arrive at an accurate conclusion one must be systematic in ruling out distractions. For example: the proper fluid to be utilized would be a Dextron II ATF product (not "gear lube"), and no one particular brand should be at fault in this issue. Also, the instance of the grinding during shifting, this being supposedly executed with the clutch disengaged, therefore engine power potential is somewhat irrelevant, thou the boxes can be for racing applications somewhat R.P.M. limited. I believe one should find the Tremec "Z" code T5 transmission a fine product, and capable behind most street intended Mustang/Shelby vehicles with S.B.F.s, with the potential of say 11 second quarter mile performances.
But, it ain't working for you, why? Well, the problem seems to be that upon the engagement effort, the synchronizer-blocker-clutch ring as part of the synchronizer assembly fixed to the counter shaft, is not clutching the 5th gear and thereby not "synchronizing" the rotational speeds of the components. Well, no s##t Einstein, but why?
It could be just defective relationship of manufacture in the applicable components, as implied previously, this is often the most difficult to establish "in the field", but is often the most comforting conclusion to those involved, other than the manufacturer. And, I wouldn't hold my breath for some determination from Mexico confirming such, and if stated otherwise, it would only be by others accepted with some skepticism. But it is possible!
More often than not (in my experience), manual transmission shifting complaints such as in this instance, prove to be clutch operation related, hence Tremecs' early concerns in this arena. One possibility, is that a relatively small rotational torque input is being applied, a sum that the other gears can, at least for now overcome, but that the 5th gear unit proves marginal in the task. One should understand that the synchronizer assemble for the 5th gear is the smallest, least effective as compared to the others, within this transmission. That understood, is the reason for my inquiry of how one established the "air-gap" value in my previous post.
Allow me to present a perhaps, simple-stupid test procedure, that seems to work most often: first, park the vehicle, engine off, on a prepared road/driveway surface with a slight incline, say 3° +/-, being held from rolling by transmission gear engagement only. Now slowly depress the clutch pedal, at what point in the pedal travel does the vehicle begin to roll if only slightly? Then continue to depress the clutch pedal, the vehicle should accelerate in its' rolling, now modulate the pedal finding the travel positioning that allows one to effect the rolling rate, above this the vehicle stops, below this there is no change in the rolling speed, this rage of pedal movement falls where in the available pedal travel? There should be a travel sum both above and below the effected range before the carpet.
Next, on flat ground, start the engine, allow a reasonable idle speed, at normal operating temperature, depress clutch pedal, place gear selector into any synchronized gear position, then place selector into the neutral position still holding the clutch pedal depressed, pause for five seconds, engage reverse. Does the reverse gear engage without grinding? Sometimes, particularly with beat-up gear sets (reverse) the gears will "blunt" and not allow engagement, but also not create any grinding, this is not our concern here, just try again. What one is looking for, is by engaging any other gear in the box with the vehicle not moving you have halted any rotation of the clutch disc, input shaft, gear sets, etc., and maintaining the clutch pedal depressed and with the pause in neutral, the observation is whether these components are re-accelerated, therefore indicating an input value as the reverse gear is not synchronized.
Also, there is driver technique to explore, but this is best accomplished with direct observation, and at times with care, as humans can be emotionally sensitive; but one topic we can preview, as pointed out previously, the 5th gear synchro is the weakest (and so is the gear set), and the differential in component speed is significant, so remember, the race is over once one chooses O.D., no speed shifting into O.D., it won't survive such abuse, allowing the R.P.M.s to drop in the execution of the shift is just good practice, besides you just traded the leverage advantage to the rear axle. ;)
Scott.
"Emotionally sensitive"? What'da mean by that? :'(
The latest T5 transmissions have synchronized reverse. Go figure. As Scott mentioned the brass synchro for 5th is tiny and the same one is used for reverse now. Another thing that troubles "me" is the 1-4 gears use carbon fiber material on steel rings and 5th and reverse are brass. the carbon fiber is fine with ATF but "I" feel ATF lacks "extreme pressure" qualities and increases the wear rate on brass. This may be why Redline MTL is favored as a lube in these transmissions. You are not the first one to have these symptoms .
rANDY
This is all great information - thanks to all! I'll keep you posted :D
Quote from: SFM6S087 on October 03, 2019, 03:38:19 AM
Hmmm... I considered following in your footsteps on this swap, but now my T-10 is looking like a keeper. Can't wait to see how this sorts out. Certainly seems like a lot of trouble for a brand new trans. Who's paying the shipping & multiple installation bills?
Steve
Hey Steve,
Actually, Tremec paid for shipping both ways for the tranny and they have asked me to submit the ticket for R&I of the transmission this most recent time, and most likely for the upcoming swap. I'm guessing they will try to pickup some or all fees for both.
Quote from: gt350hr on October 03, 2019, 02:43:04 PM
The latest T5 transmissions have synchronized reverse. Go figure. As Scott mentioned the brass synchro for 5th is tiny and the same one is used for reverse now. Another thing that troubles "me" is the 1-4 gears use carbon fiber material on steel rings and 5th and reverse are brass. the carbon fiber is fine with ATF but "I" feel ATF lacks "extreme pressure" qualities and increases the wear rate on brass. This may be why Redline MTL is favored as a lube in these transmissions. You are not the first one to have these symptoms .
rANDY
The Redline MTL has "fixed" a lot of issues in the Pantera ZF transaxles. It costs about $9,000, to go completely through that transmission at the moment. So this could save about $8950 and a six month waiting period.
Do yourself a favor. Put this stuff in your transmission. See what happens. The worst thing is nothing. There is no way an ATF belongs in a manual box. That's some sort of Vodoo wishful thinking by some pencil neck somewhere.
ATF in manual boxes is to raise the Corporate Fleet fuel consumption average because of virtually no viscosity to it. It is not a performance upgrade.
My SHO came with ATF in it. At about 60,000, it started to get funky. I swapped out the fluid for the Redline MTL stuff. It immediately shifted better, smoother, and ran quieter then it did new. It's worked in every trannie I've done. It won't stop you from breaking shift levers though. ;D
Quote from: gt350hr on October 03, 2019, 02:43:04 PM
The latest T5 transmissions have synchronized reverse.
rANDY
Randy, perhaps you might be confused between the T-5 and the T-45 or the TR-3650, but I may be wrong, and that wouldn't be a first either, but I haven't seen any? :-\
Scott.
You know . old age is not a good thing. You're right . Reverse in a T5 is "in the case" and runs off of the 1-2 slider . T45s and 56s have synchro reverse because it's in the tail housing. My apologies to those I threw off course.
Randy
Quote from: Shelby_r_b on October 02, 2019, 03:34:33 PM
Quote from: pmustang on October 02, 2019, 12:10:28 PM
Please don't read my post about T10 issues recently, I almost teared up reading your post. I had nightmares, rebuilt trans was a mess. Best of luck with your issue. Peter
I hear you, Pete! I did read your thread recently...it sent shivers down my spine. I hope you're getting things sorted out in the end. :'(
I kept the customer fully involved throughout my ordeal with this issue and gave links to threads where I asked the questions and results when suggestions were tried. I finally said I would give his deposit back and he could walk away from the car but he decided the deal was good enough and took the car as it was. I gave him a spare T10 (so the rebuilt original and a replacement one) and he was happy. He has since said that once he gets the T10 sorted (the numbers match one) he will give me back the 2nd one. I later found the receipts for the car and there was a rebuild receipt for the one in the car a short while before I got it so it was rebuilt twice and still a mess.
cheers and hope you get sorted soon. Peter
Quote from: Shelby_r_b on October 02, 2019, 02:49:36 PM
I just got off the phone with Tremec, and they are going to do a 1 for 1 swap.
So, I'll drive it for now, double clutch it into 5th, and wait for the new tranny to come. The saga continues! ::)
I would suggest doing as much "home-work" as is reasonably possible with the existing unit in place, with the intention of ruling out all other possibilities, leaving one with the conclusion of only the box being at fault. Remember, someone already practiced throwing parts at it, to apparently no avail, and I'm not sure if just changing the entire unit vs the parts within is much different in effect, but possibly. And one also doesn't want to just accidentally thru an inconsistent R & R process have the problem disappear, as this may only prove temporary, and then you may not at that point have any support remaining from the manufacture(s). ;)
Scott.
Ruben, Scott brings up a good point. A few bottles of REDLINE MTL (https://www.redlineoil.com/mtl-75w80-gl-4-gear-oil) is worth a shot....and, while they've been very supportive, what's going to be the warranty on the replacement? Hopefully, not an "Oklahoma Guarantee" (30 miles or 30 minutes, whichever occurs first) :)
putting me in a different lubricant May mess with the warranty and they might refuse to touch the tranny again. I would talk to Bruce at modern Driveline as he has been working with these transmissions for over twenty years and even Shelby went to him for help with putting newer style transmissions in some of their vehicles.
https://www.moderndriveline.com/
Sincerely, Roy Richards
Thanks as always to all for the input! :D
Quote from: TA Coupe on October 04, 2019, 10:19:16 PM
putting me in a different lubricant May mess with the warranty and they might refuse to touch the tranny again. I would talk to Bruce at modern Driveline as he has been working with these transmissions for over twenty years and even Shelby went to him for help with putting newer style transmissions in some of their vehicles.
https://www.moderndriveline.com/
Sincerely, Roy Richards
You won't need a warranty on a transmission that works. The fluid can always be removed. It isn't a permanent modification. ATF does not have the right friction modifiers for the manual's syncros.
Then again, you want brass syncros, not paper ones.
We were a Tremec sales, warranty inspection & repair facility for many a year; that was until their marketing dept decided to concentrate their ties to regional "Elite" dealers and our region was routed to someone who hadn't sold one tenth the number of units we had, nor did they provide any additional services, but hey, that's what pals are for right? But anyway, I'll say it again, Dextron II type fluid is correct, any value difference between one product vs. another is not relevant, but do not put "gear-lube" in the box as it is inappropriate (and will cause failure!), and upon inspection disassembly it will be witnessed, and would be grounds to void any warranty responsibility. ;)
Scott.
In a T5 , carbon fiber synchros are excellent. 5th is the only gear that uses a brass "blocker ring".
Scott is right. Dexron II only. I've been running my T-5 (Z) trans behind 419 lb-ft Roush engine for 6-7 years with no problems. It's not the ideal trans but it works fine, even for a lot of "spirited" driving. It's also small enough I didn't have to enlarge the shifter hole or hack anything on my '66 GT350 (SFM6S264).
Greg D.
So, I think this chapter is finally closed! After sending back my original T-5 that would grind going into 5th gear, having them "rework it", sending it back to me, only to have the same problem arise after a few 5th gear shifts, and now finally getting a whole new transmission installed - all is well! :D
What's interesting is that the shop noted the fluid drained from the old (original) T-5 looked terrible.
Hopefully, this is the end of the story.
Thanks for sharing the details of your T-5 experience. Now for the miles & smiles.
Steve
Quote from: SFM6S087 on November 25, 2019, 03:54:15 AM
Thanks for sharing the details of your T-5 experience. Now for the miles & smiles.
Steve
Exactly! 👍🏻
One final post to close the loop: TREMEC has done an outstanding job of completely rectifying the situation to my full satisfaction. They did an amazing job of making everything right. And, the new transmission continues to exceed expectations.
Thanks again to all!
The follow up is much appreciated.
Thats wonderful news!
Personally, I think this may have been a semi-isolated instance. Either way, I wouldn't be afraid to use the T-5 again, even if I ran into problems, given how well they handled things in the end.
A T-5 is not as weak as everyone says it is. Don't abuse it and it will be fine. I personally made many high eleven second passes in a 3,800# Thunderbird with zero problems. No power shifting though! I put a Tremec 3550 non TKO in it and snapped the output shaft off.