Passon or Tremec TKO 5 speed gear box consideration.

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Gregor

Gregor

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Hey guys, I would appreciate your opinions. My car is a 70 Dart with an A833 4 speed. I have a 3.91 gear in the rear end. Currently at 60 mph the engine is turning 3150 rpm. I plan on keeping this car for a long time and do enjoy driving on longer highway trips. That said I am going to put a 5 speed gear box in it. I am looking at the Passon Performance A855 or the Tremec TKO 5 speed. Does anyone have any insight as to which product will be the simpler one to install. Passon claims that their gear box is a direct bolt in with zero modifications. I have read that the Tremec TKO may need some mods. Also I am in Cleveland Oh. Is there anyone in my area who would be willing to help me with this process once I get the new gearbox? I would be able to pay you for your time/travel expenses.
Thanks in advance for your help.
 
Last I heard, there is a 2 year wait list for a Passon 5 speed.
A Gear Vendors .78 OD would give you 2457 RPM at 60. Pretty much a bolt on with a little wiring power and a switch plus since it adds length, you need to shorten your drive shaft.
Here they put one in the Road Kill Hemi Super Bee.


If you don't mind cutting your floor, Silver Sport's T56 Magnum 6 speed with double OD for Mopars is really sweet.
Articles - TREMEC TKO, TREMEC Magnum & SST A41 Conversion Kits for 1964-1976 Dart, Valiant, Barracuda, Duster, Demon, & Scamp
T56_Top_flat_4.png
 
Have you checked with Passon on current price and lead time? I'm number 181 on the list with an early A-body and Jamie is not ready to give me an estimated delivery time. He is getting a few units out to customers now. I'm guessing it will still be a couple of years before I have one in hand. I've heard there are currently around 400 folks on the waiting list. His tranny should surely be worth the wait though.
 
I know a guy who put the passon in his car and he said it was a work of art and the single best thing he did to the car, a 400 big block stroker build in an E body.

That said, like others say the cost is apparently Big $. And maybe getting one is the biggest problems. Even if he was to get you one what if it needed service or warranty or whatever... Might be better off with a tremec offering?
 
Have you thought about Passon's 4 speed overdrive ? On a budget ? We put one in a 73 Cuda and it worked out great.That will be a direct bolt in and all you would have to buy is the tranny and maybe the shift arms.I had a TKO in a B body and a A body..Yes the floor needs to be worked.Never did like the way it shifted, and it would grind during a power shift.Tremec may have fixed that by now.What we found out you always run out of road when you got your foot in it before you ever hit high gear.So it was 1,2,3,OD for me ! Just something to think about but, if the funds are there,,,,Shoot for the Stars !!
 
grimreaper said:
Have you checked with Passon on current price and lead time? I'm number 181 on the list with an early A-body and Jamie is not ready to give me an estimated delivery time. He is getting a few units out to customers now. I'm guessing it will still be a couple of years before I have one in hand. I've heard there are currently around 400 folks on the waiting list. His tranny should surely be worth the wait though.
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I spoke with Jamie the other day. He quoted me $5300 for the 5 speed with a 12 month wait time. That's ok with me cause I need that time to get the cash together without taking a loan.
 
Darter6 said:
Have you thought about Passon's 4 speed overdrive ? On a budget ? We put one in a 73 Cuda and it worked out great.That will be a direct bolt in and all you would have to buy is the tranny and maybe the shift arms.I had a TKO in a B body and a A body..Yes the floor needs to be worked.Never did like the way it shifted, and it would grind during a power shift.Tremec may have fixed that by now.What we found out you always run out of road when you got your foot in it before you ever hit high gear.So it was 1,2,3,OD for me ! Just something to think about but, if the funds are there,,,,Shoot for the Stars !!
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I am leaning towards the Passon 5 speed. I was thinking about the 4 speed overdrive. Jamie told me that he would take my 833 box and put his gear set in it. However that only puts my engine at 2425 rpm for 60mph. Since I'm thinking that I'm gonna keep this car for a long time I figure that eventually premium gas will be above $4 per gallon. By getting the 5 speed which will give me 60mph at 2100 rpm I'll save gas in the long run thus saving cash down the road. Pay for it now or later plus with the 5 speed less wear and tear on my engine. Thanks for your opinion.
 
grimreaper said:
Have you checked with Passon on current price and lead time? I'm number 181 on the list with an early A-body and Jamie is not ready to give me an estimated delivery time. He is getting a few units out to customers now. I'm guessing it will still be a couple of years before I have one in hand. I've heard there are currently around 400 folks on the waiting list. His tranny should surely be worth the wait though.
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Spoke with him the other day. He said $5300 and a 12 month wait. I'm saving for it now. I really don't want to cut the floor so I'm thinking the TKO is out.
 
'Cuda_ragtop said:
Last I heard, there is a 2 year wait list for a Passon 5 speed.
A Gear Vendors .78 OD would give you 2457 RPM at 60. Pretty much a bolt on with a little wiring power and a switch plus since it adds length, you need to shorten your drive shaft.
Here they put one in the Road Kill Hemi Super Bee.


If you don't mind cutting your floor, Silver Sport's T56 Magnum 6 speed with double OD for Mopars is really sweet.
Articles - TREMEC TKO, TREMEC Magnum & SST A41 Conversion Kits for 1964-1976 Dart, Valiant, Barracuda, Duster, Demon, & Scamp
View attachment 1715001177
Click to expand...

Thanks for the video links. Good information.
 
The thing to remember on the t56 is that it is a double overdrive. 5th gear is around a .74 and 6th is .50. You will have to do some serious freeway to use those gears. Both the TKO and the T56 require some cutting to install. The T56 takes up a lot of real estate. If you are comparing prices between these and the Passon unit, figure in the cost of fabrication also.
 
Revhendo said:
The thing to remember on the t56 is that it is a double overdrive. 5th gear is around a .74 and 6th is .50. You will have to do some serious freeway to use those gears. Both the TKO and the T56 require some cutting to install. The T56 takes up a lot of real estate. If you are comparing prices between these and the Passon unit, figure in the cost of fabrication also.
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You can choose Close or Wide ratio T56.
T56 Magnum Gear Ratios
Close: 2.66, 1.78, 1.30, 1.00, 0.80, 0.63
Wide: 2.97, 2.10, 1.46, 1.00, 0.74, 0.50

Passon A-855
2.64, 1.92, 1.40, 1.00, 0.70

T56 is definitely the most expensive and requires tunnel mod. They say also say not to exceed 450 HP in 4th gear.
I like the idea of a straight swap with Passon and that it is a couple thousand $$ less than a T56 all in, but at $5300 the A-855 is still $2505 more than a $2795 GVOD.

Merry Christmas!
 
'Cuda_ragtop said:
You can choose Close or Wide ratio T56.
T56 Magnum Gear Ratios
Close: 2.66, 1.78, 1.30, 1.00, 0.80, 0.63
Wide: 2.97, 2.10, 1.46, 1.00, 0.74, 0.50

Passon A-855
2.64, 1.92, 1.40, 1.00, 0.70

T56 is definitely the most expensive and requires tunnel mod. They say also say not to exceed 450 HP in 4th gear.
I like the idea of a straight swap with Passon and that it is a couple thousand $$ less than a T56 all in, but at $5300 the A-855 is still $2505 more than a $2795 GVOD.

Merry Christmas!
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Thanks for your assessment of these choices. Given I don't want to cut the floor and want my install to be as simple as possible I am going with the Passon 855. Now the wait begins but it will be worth it. Merry Christmas my Mopar friend.
 
I also looked at the t56 swap option when I was considering an overdrive for my dart.
I would love the a855 from passon but the wait is long. I like to puzzle things together.
With the t56 the cutting and fabricating is not a problem for myself. The price tag is about the same for the t56 swap or the a855
So it's basically the same.
Myself the 855 swap is easier because no fab work.
I decided I will stick with hemi overdrive gear swap since I have the cases that need rebuilt anyways and I want to keep my hurst ramrod shifter.
I keep stumbling back to the t56. If only I could stumble on a cheap t56 then I would go that direction
 
Sounds like you are going with the direct bolt-in Passon. But whatever you decide, I can help with the installation if needed.
 
KosmicKuda said:
Sounds like you are going with the direct bolt-in Passon. But whatever you decide, I can help with the installation if needed.
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Man that would be great. I was planning on going with the Passon 855. Now I am getting advise on other customers having problems with those and the 12 month wait time I was quoted turning out to be over two years. Do you have any opinion on the Gearvendor option? They do seem to back up their product and have been around a while. I see your in N. Ohio. What part? I'm on the west side of Cleveland. We'll have to meet up after the winter passes.
 
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there is a guy floating around here that has had nothing but issues with the passon unit.. better do your homework before dropping that kind of coin.. i also don't think guys are getting them at their "estimated" times frame..
 
abodyjoe said:
there is a guy floating around here that has had nothing but issues with the passon unit.. better do your homework before dropping that kind of coin.. i also don't think guys are getting them at their "estimated" times frame..
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Good to know. I sure would like to talk to that guy. Don't suppose you can remember who he is?
 
For gear vendors and 4 speed you need to change over to a "b" body mainshaft and use their tails haft housing. Shorten driveshaft which I have read is not optimal for unerversal joints. (Don't quote me)
Also heard it's not good for switching at high torque or horsepower areas and you will never shift from 1 to 1 od then 2 then 2 od etc. So the shift split is a moot point.
I like the t56 idea more and more with 6 gears all contained with one high price. I believe you are at same price range when going for t56 and gear vendors
 
i know a couple guys running it and they love it.. OD ratio isn't as good as some others but it still makes a 3.55 into a 2.76 i think it is.
 
abodyjoe said:
i know a couple guys running it and they love it.. OD ratio isn't as good as some others but it still makes a 3.55 into a 2.76 i think it is.
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Well I think I'm gonna keep my name on the 855 waiting list. On the other Moparts forum Jamie himself addressed some of the production issues and I believe he is about to start getting caught up. Also I read that it issue of some of the earlier units popping out of gear has been fixed. I need at least a year to save the cash up anyway.
 
I think Jamie has provided a solution for the bugs that have shown up. The latest was a popping out of gear issue which he solved with a different slider. He now tests every transmission before it is released. The "estimated time" continues to be an issue though.
 
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