Slip and slide transmission

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indirect_connection

indirect_connection

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Finally took my maiden voyage have after swapping in a mildly built 360 in place of the old 273. Engine runs great, but I seem to have transmission issues that were not present before.

Any significant throttle seems to cause it to start slipping on the 1-2 shift. Let off the throttle and the shift completes. The first trip around the block was with a low fluid level, my fault for checking in park and not in neutral. It took 2-3 quarts to bring it up to level. The second trip was maybe 1-2 miles, but no better.

Now one issue may be the kick down linkage. I switched to cables, but the ratio on the Holley carb is off. So I have 100 percent kick down at WOT, but at idle to 1/3 throttle the cable stop isn't even contacting the linkage. Now I've seen conflicting info. Some say the linkage is critical to part throttle shifts, others say it does nothing except at WOT.

Finally, I drained the converter when I pulled the motor. I topped the system off with AutoZone STP Dex/Merc.

So, what's the most likely cause of my issues? Kick down adjustment, fluid, driving while fluid is low, or just exceeded the horsepower limit of a 50 year old trans.

Note: Trans previously handled WOT with the 273 no issue. I did not exceed 1/2 throttle after the swap. No more than 3k RPM.
 
Sounds like tv linkage issue, with out the correct linkage on the throttle arm of the carb you will not get proper line rise at lower openings and trans will slip and burn up in short order.
Proper throttle linkage is critical to any mopar trans to live
 
Yes the throttle pressure should increase with slightest throttle/rpm increase. The term "kickdown" is what causes confusion/misconception. Its not all about wide open throttle or a passing gear.
Although not related to throttle pressure, the nose of a early 273 torque convertor is too small in a 360 crank. You may or may not have needed a bushing there.
 
The linkage is critical to anything that transmission does. Period. End of story. Roger Wilco. Over and out. Find new informants. Some of the ones you have are idiots. If it's slipping that badly, The damage is done. It's time to pull it. It probably didn't show up before because you didn't have enough power to make it slip. Now you do. The Torqueflite transmission MUST have that throttle pressure linkage installed. Must, must, MUST, MUST!!!!! It's not like a Chevy and some Fords where you can throw the kickdown linkage or cable in the ditch......and even with them it's not a good idea, yet ALL the Chevy guys leave it off. Dumbasses. Not you. Them. You just didn't know. They have no excuse. lol That's the correct name for it. Throttle pressure linkage. It operates by manually increasing the throttle pressure as the gas pedal is depressed. More gas pedal, more throttle pressure. The purpose in increasing throttle pressure to the transmission is to increase the transmission's LINE PRESSURE so that the clutch packs are held more tightly together as more engine RPM (power) is transmitted through the transmission. Without that all important throttle pressure linkage to increase that line pressure, the clutch packs have very pressure holding them together and will slip. As I said, if yours is slipping as described, get the tools out. It's done. Once rebuilt, find the proper throttle pressure linkage. I would use the OEM stuff, as my opinion of the Lokar is not very good....and yes, I've seen and installed some for other people that just HAD to have it and I think it's junk. Chrysler got it RIGHT when it came to transmissions. Good luck!
 
indirect_connection said:
Finally took my maiden voyage have after swapping in a mildly built 360 in place of the old 273. Engine runs great, but I seem to have transmission issues that were not present before.

Any significant throttle seems to cause it to start slipping on the 1-2 shift. Let off the throttle and the shift completes. The first trip around the block was with a low fluid level, my fault for checking in park and not in neutral. It took 2-3 quarts to bring it up to level. The second trip was maybe 1-2 miles, but no better.

Now one issue may be the kick down linkage. I switched to cables, but the ratio on the Holley carb is off. So I have 100 percent kick down at WOT, but at idle to 1/3 throttle the cable stop isn't even contacting the linkage. Now I've seen conflicting info. Some say the linkage is critical to part throttle shifts, others say it does nothing except at WOT.

Finally, I drained the converter when I pulled the motor. I topped the system off with AutoZone STP Dex/Merc.

So, what's the most likely cause of my issues? Kick down adjustment, fluid, driving while fluid is low, or just exceeded the horsepower limit of a 50 year old trans.

Note: Trans previously handled WOT with the 273 no issue. I did not exceed 1/2 throttle after the swap. No more than 3k RPM.
Click to expand...
Probably the first thing to do is take a clear photo of the kick down linkage on the drivers side of the carb and post it here. We can't see what you are talking about until you post it here.
 
Could always disconnect the cable and tie it all the way pulled and see how it feels about that.
It should shift late and hard with no engine braking in first.
Gotta agree with RRR here, as pretty much any slipping burns the forward clutch discs.
It’s worth a try.
 
TV pressure from the "kickdown" is just as important in a GM and Ford as a pre ptk chrysler. Some earlier Fords are even more important. Sorta like a 700r4 or AOD; if the kd isn't hooked up at all, it won't even shift. Easy to figure out just by looking at the kd arm inside the trans; where it doesn't even touch the valve at idle.
 
I can get a photo when I get home, but you the linkage looks like this. Just a much larger gap at idle. I researched here the best I could before install, and multiple people said that it worked fine with the gap. Here is an example of a thread: Lokar Kickdown Adjustment? KICKDOWN LEVER STUCK


Regardless if I need to rebuild or not, I need to get the linkage worked out. I was hoping to at least be able to use it this summer to attend some cruise-ins.
Kickdown.jpg
 
You can try getting it right, but even if it does shift better, there's damage there. Good luck with it, whatever you do.
 
Sorry to say that even one drive with screwed up throttle pressure linkage, the damage is done. You can correct the linkage and get some life out of it, buy depending on how much you drive it will probably die within 6 months to year. Ask how I know.... Just make sure at full throttle it's all the way back and tight. With the lokar cable you need to make sure it starts moving instantly as soon as you touch the throttle. Also the cable will stretch so account for that and keep an eye on it. You may need to change to a different ratio lever on the trans or at least drill holes to get the pull right, it's all about geometry. Please don't listen to people who adjust it to move there **** points around, this can do more harm then good.

Also it depends on the horse power of your engine. The more power you put to it, the more pressure your trans will need. So yours may not be happy with the slack... The slack can be ok, depending on application, as long as it pulls the trans lever as far back as it will go at full throttle or close to it.
 
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RRRis correct . I suggest that you adjust the kd cable and see what happens . I also suggest that you adjust the high gear band . It's in the Factory Service Manual . If it won't help r&r the tranny and rebuild with ALL the upgrades . converter too
 
The engine swap was this winters project. If I can make it last till next winter I'll be happy. Chances are it won't be more than a couple hundred miles. As soon as I drive it a few times I tend to start the next project and put it back out of commission.

Speaking of upgrades, what's a good recipe for (an optimistic) 400 horsepower? Standard rebuild and shift kit, or upgrade to Red Eagle clutches? Any hard parts need an upgrade?
 
indirect_connection said:
The engine swap was this winters project. If I can make it last till next winter I'll be happy. Chances are it won't be more than a couple hundred miles. As soon as I drive it a few times I tend to start the next project and put it back out of commission.

Speaking of upgrades, what's a good recipe for (an optimistic) 400 horsepower? Standard rebuild and shift kit, or upgrade to Red Eagle clutches? Any hard parts need an upgrade?
Click to expand...

Anything's possible. It might work out and be ok, but I don't wanna paint you a rosy picture when it probably ain't gonna happen. lol
 
indirect_connection said:
The engine swap was this winters project. If I can make it last till next winter I'll be happy. Chances are it won't be more than a couple hundred miles. As soon as I drive it a few times I tend to start the next project and put it back out of commission.

Speaking of upgrades, what's a good recipe for (an optimistic) 400 horsepower? Standard rebuild and shift kit, or upgrade to Red Eagle clutches? Any hard parts need an upgrade?
Click to expand...
Thats not many miles, you'd probably be fine but no guarantees, just like RRR said.
What year is your trans? I would get a red alto deluxe kit from transparts warehouse for the correct year. Grab the solid red band and double wrap band from A&A, A&A sells misc bushings you may need too. Then a reverse wound clutch pack spring from ati. Finish it with a transgo stage 2 and she'll be great. maybe add a billet strut rod and a sonnax rear servo.
 
The car is a 68. Don't know if the motor and trans are original, but the 273 has hydraulic lifters so it should be the later engine. Are there major changes to the later ones? I noticed that some rebuild kits are split into pre '72 or later.
 
You can tell by the rail the trans pan bolts too, I believe its on the drivers side, not the drinkers =), you tell me what that number is and ill tell you the year. There is seal and bushing differences. Certain passage ways changed. Size of the servos changed as well. Valvebodys changed but are mostly compatible. Did it have partial throttle kickdown? If it does its not a 68 for sure unless someone swapped the vb, read my book, ptk was 69 for v8 904s. Should be a partial or full vin on the rail too. Ill help you pick parts as well if you want. Ive rebuilt 904s and they have all worked perfect.

numbers.jpg
 
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Finally got some time to tinker with it. Turns out the gap in the kick down linkage was only there because the arm on the trans wasn't all the way forward. Used a bungee cord to pull the arm all the way forward and it took all slack out of the cable. I started to try and adjust the front band, but it is not easy in the car. Here are pictures of the linkage (no bungee cord) and pictures of the ID number on the pan rail. Can anyone confirm the year of the trans?
IMG_2012.jpg
IMG_2008.jpg
 
indirect_connection said:
Finally got some time to tinker with it. Turns out the gap in the kick down linkage was only there because the arm on the trans wasn't all the way forward. Used a bungee cord to pull the arm all the way forward and it took all slack out of the cable. I started to try and adjust the front band, but it is not easy in the car. Here are pictures of the linkage (no bungee cord) and pictures of the ID number on the pan rail. Can anyone confirm the year of the trans? View attachment 1715711701 View attachment 1715711702
Click to expand...
That trans matches your car. 1968, 273 passenger car std.
 
Ok, been doing some research. Looks like the 904 used with the 273 came with the single wrap rear band. Some threads indicate that the double wrap requires a different case? So do I need to keep what I have, or can I upgrade to the double wrap with the stock case?
 
indirect_connection said:
Ok, been doing some research. Looks like the 904 used with the 273 came with the single wrap rear band. Some threads indicate that the double wrap requires a different case? So do I need to keep what I have, or can I upgrade to the double wrap with the stock case?
Click to expand...
I believe thats only with /6 904s. V8 904s should have a double wrap cast band, someone please jump in if im wrong here. Make sure you get a red lined cast double from a&a. These are the two I use.
904 2nd Gear Band Red Racing Solid with Grooves *1.375" Wide - A&A Transmissions *2nd Gear Band
904 band - A&A Transmissions *Reverse Band
If its actually a single wrap, then this is what I would use.
904 Reverse Red Racing Single Wrap with Grooves core $25.00 added - A&A Transmissions
 
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CudaFactHackJob said:
TV pressure from the "kickdown" is just as important in a GM and Ford as a pre ptk chrysler. Some earlier Fords are even more important. Sorta like a 700r4 or AOD; if the kd isn't hooked up at all, it won't even shift. Easy to figure out just by looking at the kd arm inside the trans; where it doesn't even touch the valve at idle.
Click to expand...

Well, you and I know that. My point was, that's not peoples perception. They think just because this guy over here does something, they can too. Typical follow the sheep over the cliff mentality.

Not referring to the OP, he just "didn't know". Big difference.
 
Quite easy to determine if your 904 has a single or double wrap band. Look at the rear of the case on the passenger side. If there are 2 strengthening ribs above the low/reverse piston bore, you have a double wrap band. If these ribs are not there you have a single wrap band.

40825786nh.jpg
 
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