About our transmission...

[wallew]

On another topic, rizzo said something like "you aren't looking at this problem correctly".

While I was driving down the highway the other day, that statement became an epiphany.

I've always felt that if the tranny was a six speed or an eight speed, life on the highway would be much nicer, and so would my mpg. We all know that no one has come up with replacement diff gears and even if they did, would you want to give up the lower end? You can replace the tranny with an eight speed. I THINK Trango did that. So here's the question.

Could the gear box 'innards' be replaced with a six, seven or eight speed? If so, would the costs be prohibitive? Or is there some company out there that could do that? Aside from giving us better mpg on the highway and a little better top end, it would mean having a 'newer' transmission that might not have some of the hard to get parts of a forty year old + tranny design.

Just curious folks. SO, have I completely lost my mind? Probably so, but...

jim

 

[rdixiemiller]

As far as I know, swapping guts in the tranny is not an option. There are trannies with more speeds that will bolt up, but they require moving the t-case back. There is a thread on the 5 ton forum about swapping in an 8 speed. That tranny should bolt up to the LDT-465 with the correct bellhousing. I don't know how much longer it is than the stock 5 speed, so I can't vouch for the t-case move requirement.

 

[clinto]

You can't just swap gears in the trans. Forst off, the case would have to bigger to accomodate them. Technically, if someone had the money, they could tool up and make new gears to relace 4th gear (which is the overdrive gear you're in on the highway, not 5th) but that would be cost prohibitive...........

An entire trans swap is on order....

 

[wallew]

clinto,
Not arguing but am now very confused. I thought 4th gear was 1:1 and 5th was .73:1 (.78:1?).

So what am I missing? Sorry for the bother, but I just love this kind of stuff.

jim

 

[clinto]

Wallew,

In 'high" gear, in any manual transmission, the input shaft is locked to the output shaft and the countershaft is out of play, so to speak. That's why a lot of people use to call high gear "direct". If it's locked, it is acting as a driveshaft in between the back of the engine and the transfer case/driveshaft, etc.

In order to have an overdrive (or underdrive for that matter), you have to have a pair of gears turning against one another.

So what the manufacturer's did was make 4th gear overdrive and swap the shift pattern. Ever wondered why your multifuel shift pattern is funny, in that when you shift, 4th gear is where 5th normally would be, and then for 5th gear, you shift up to where 4th normally would be? That's becuase in your truck, 5th gear IS 1:1 and 4th gear is .78:1. I hope that makes sense.........

Every manual overdrive trans is like this, but some have a "normal" shift pattern. When Chrysler introduced their OD version of the A-833 4-speed, they got around this by inverting one of the shift levers that attach to the shift forks.....that way, when you are putting the shifter in the 4th gear location, you are actually putting the transmission in 3rd gear, thus allowing the OD.

So technically, in the 3053, 5th gear is 1:1 and 4th gear is .78:1. That's why the shift pattern is the way it is.



More:
http://auto.howstuffworks.com/transmission5.htm

 

[Recovry4x4]

Clinto's expanation is dead on. Just to give a physical example, consider the 3052 transmissions in the gasser deuces. It is the exact same transmission as in the mutifuels with the exception Clinto mentioned. It even has the convetional "H" shift pattern like you would expect. The Spicer engineers swapped the OD gear into where the 4th gear was and made it the 5th gear. One needs to be aware of this if wading through a stack of deuce transmissions. If the data plate is missing you need to put the tranny in gear and feel your way through grabbing both the input and output in many gears and spinning the tranny. [/code]

 

[gringeltaube]

From the manual:

 

[rizzo]

this is a very informative and interesting thread.

 

[wallew]

clinto,
While I followed what you said, NOW I am very, very confused. IF 5th gear is 1:1 (which I AM NOT arguing) what does it do to drive ratio? If 4th gear is .78:1 then I should be doing my highway driving in 4th?

I AM SO CONFUSED and all I want to do is understand it. I am NOT an engineer.

As I tell everybody, my wife is the brains in our family and I'm the muscle.

So, break it down a little further if you can. I do get what you are saying so far, but am confused about the FINAL drive ratio. IF 5th is 1:1 is it the OD? Or is 4th the OD? And which gear should I be driving in on the highway for best mpg (lower revs)?

Sorry dude, just an old guy who sometimes gets confused to easily. Thx for the explanations so far. jim

 

[rmgill]

Wallew, they're just being conservative. 5th in the shift pattern on the gassers is straight through ratio. On the Multi-fuels it's 4th gear. The multi-fuels having a further overdrive.

Gasser
R 2 4
|-|-|
1 3 5

Multi-fuel
R 2 5
|-|-|
1 3 4

The design of the transmission allowed the change of one ratio set of gears and dogs to get an overdrive with out changing out the entire guts of the transmission.

 

[FSBruva]

wallew-

Clinto was talking about 4th being OD *only if you did not already know that 5th in a multifuel is forward and to the far right.*

In a traditional shift pattern, (or, if you did not have the handy dandy data plate) what you thought was 4th gear is actually OD=best mpg on highway. So, what you know to be 5th gear according to the data plate is in the "4th gear spot" on the shift pattern.

Just go get any ordinary citizen, have them start in first, shift up through the gears, and get a big surprise when you try to go from 3rd to "4th" and suddenly you engine bogs & nearly stalls.

Matt

 

[gringeltaube]

3053A tranny

Rmgill,
You put it very clear! Actually only 4 components (gears) are different between both model trannys (see red circles in drawing below). I had made several gear sets locally and converted 3052 to 3053A before I could import whole transmissions from USA.

 

[Trango]

Gringel, You rock.

Jim, the 9 or 13 speed project has been put on hold for now. I am going to use the .695 OD 5spd tranny I have for a while, until I can dedicate a couple of weeks to moving the transfer case and brake stuff back.... which needs to get done to fit anything longer-larger in there. I had a tranny I was going to use, but I was able to put it back in the pool and wait for a better one to come along.

There's only one tranny where you can actually add gears - it's the spicer convertible series. You can essentially bolt on another countershaft or set of gears or something to literally add gear choices. I have looked at the docs, but it wasn't for me at the time so I don't happen to recall the specifics.

Best,
Bob

 

[Polverone]

NOW I am very, very confused. IF 5th gear is 1:1 what does it do to drive ratio? If 4th gear is .78:1 then I should be doing my highway driving in 4th?

Uh.....you also lost me here. 4th gear is higher ratio than 5th?
What is the ratio of 3rd gear? That would get my ducks in order.

Interesting topic. I like where yer going with it.

What little genius I had just melted into ear wax.

 

[rdixiemiller]

OK guys. The gear numbers are arbitrary! On the original 3052, the gear pattern was
R 2 4
|-|-|
1 3 5

In this case, 1st is the lowest reduction, followed by second, third, and fourth. Fifth gear is direct drive, or high gear.

When the tranny was redesigned into the 3053A, The shift pattern was changed to this
R 2 5
|-|-|
1 3 4

The lowest gear reduction is first, followed by second, and third. Fourth gear is 1:1, or direct drive. Direct drive is in the same place it always was.
Fifth gear is now overdrive. This explains the difference in shift patterns. The original fifth gear became the new fourth, and the old fourth became the new fifth, if that makes sense.
Regardless, you just need to follow the shift pattern on the dash and you'll be fine.
I don't find the multifuel tranny shift pattern odd, I drove a 1964 IHC 1600 with the same pattern for a couple of years. Might even be the same tranny, because there was a big hole between third and fourth, just like the multifuel tranny.
One way to explain the multifuel tranny is to say you have a six speed that has a missing gear. 1,2, and 3 are good. 4th is gone, so you skip to 5th gear, (a big gap) then 6th.
That is how they drive, anyway.

 

[wallew]

WHEW!!

Thx guys. I DO HAVE the data plate with the shift pattern and actually LIKE having the 4th gear at bottom right. and fifth top right! It makes it unique enough that people go "HUH" when they look at that data plate with the shift pattern.

So, all is as it should be in my world. I did understand the 'reversed' 4th and 5th gears ALMOST immediately. I did a double take the first time and then thought it was odd when I test drove the truck.

BUT NOW, I think it's a great set up. Having to do the little 'h' in shifting from 3rd to 4th has become 'fun'. And I have been working my left leg so much with the clutch my knee hurts for about half a day if I forget the advil.

THANKS GUYS. It's clear. I just thought we were discussing the tranny gears as they are shown on the data plate. IT IS a very complex concept the first time you see it. But way kewl design.

Trango, contact me. Want to discuss that MV party at my place. Gotta coordinate with you, DrFoster, RandyLBarnes and we might be able to talk other Colorado residents to stop by. If you don't have my number, email me. If there is ANYONE ELSE who wants to come to the party, I will post a timeframe here in the next few weeks. I live in Denver and it would be MONSTER KEWL to park about ten or fifteen MV's in our cul-de-sac. Could be quite a draw for all the neighbors...
jim

 

[gringeltaube]

gear ratios

See attachment.
Let's try it with the term "speed", not gear or shift lever positions. For every complete turn of the output shaft, the input shaft has to make 5 revolutions in first speed, almost 3 in second speed, and so on.
In 4th speed (1:1) both shafts are connected (power goes straight trough) which means less wear, noise, heat from other components. With our 2600 rpm multifuels in 4th we would only do 45 mph, not 57. Good that there is a 5th speed ,OD which converts the 2600 crankshaft rpm into 3275 (!!!) driveshaft rpm. (poor oil seals, bearings, U-joints, etc).

Hope this helped!

 

[wallew]

Gerhard,
Thx bud. I have always figured it was something like that. I'm a visual kind of guy.

Now to REALLY screw this up 'gear ratio' wise. What happens to those ratios when you go with Super Singles? Do they go up or go down?

For example, I'm about to go with 275 80R 22.5's which are considered 'low profile' at approximatley 41 inches tall. Way kewl directional tread. So I know my top speed will (should?) increase a little.

Past that I was just hoping for a tiny bit more control and a little smoother (not softer) ride.

 

[FSBruva]

Wallew-

Unless your 'low profile' tires have a unique set of installation instructions, the internal gearing of your transmission should remain the same.

Matt

 

[wallew]

FSBruva,
NOPE just plain old tires. And that's what I thought. But was wondering. THX! jim