Swap Mack T318LR tranny for Eaton 18 tranny

[Vac-Daddy]

I was hoping on getting some insight on doing a swap, Mack 18 to Eaton 18. My Mack tranny needs to be replaced and parts are hard to get and very expensive. I can purchase a very good Eaton 18 For quite cheap from a good buddy of mine. What's everybody's thoughts, please help? 2007 Mack Granite.

[Geoff Weeks]

boy, did we get "off in the weeds" on this thread.

[Joey Mack]

sure did..   But,,,, thats what we do here..  I did ask some off track questions that you guys were willing to answer...

[Joseph Cummings]

1 minute ago, Geoff Weeks said:

I just put my numbers into Spicer's driveshaft calculator and it spits out what I need to know. Critical and 1/2 true critical.

When I was in school we didn't have "driveshaft calculators". We had to do the math with a pencil and paper and a slide rule. I had to walk there in torrential rain wearing a yellow rubber rainsuit and galoshes. Uphill both ways

[Geoff Weeks]

Yeah, well he had to do it in snow!

[Joseph Cummings]

Starting at the lower right and ending with the upper left (I know its kinda Chinese or something) is how a power transmission shaft tries to distort as you hit each critical speed.

Think of an out of balance tire. You hit a speed and it's bouncing, speed up and it smoothes out, then you hit another bouncy speed and so on

 

[67RModel]

The Mack transmission might seem more expensive than the Eaton on the surface but I can almost guarantee it would be cheaper, all things considered, to just replace what you have. Either by overhaul or just getting a reman unit. Call Weller or similar order exactly what you have delivered to whatever shop you use. Once it gets in they can have it swapped out and everything switched over in a day and you can be back to work the next. Then send your old one back as a core. I would forget about the Eaton in your case.

[Vac-Daddy]

On 12/21/2024 at 6:25 AM, fjh said:

I have a concern here Is your buddys trans Out of a mack? The bell housings is a diffrent set up for mack and western star ! being a 2007 this is a change over year are the rear  engine mounts  actually on the engine or the trans!?Your doing the right thing by going eaton BUT you need to do your home work as you are doing here! 

Started the swap. It's actually quite common I found out, in my city.  Found the proper bellhousing, Mack motor to Eaton Fuller. Went and bought the 18 speed Eaton today. My PTO  should bolt right up. i will have to get a different drive shaft. And a few other little things 🙂 i'm lucky because my truck came with either a maxitorque or an Eaton 🤔 the price on a new maxi torque for me is 25k Vanadian. Ordered out of the USA, then I would have to pay shipping and taxes, plus clutch plus install lol no thank you! I can purchase a brand new Eaton Fuller off the shelf in my city, where I live forIMG_20241223_183829.heicIMG_20241223_183825.heic 7k. It is a no brainer 🤯

[Joey Mack]

I see it has bores for the release fork for macks fork location.. in the bell housing... good deal

[Vac-Daddy]

17 minutes ago, Joey Mack said:

I see it has bores for the release fork for macks fork location.. in the bell housing... good deal

I'm pretty excited and I'm going to keep everybody up-to-date on this post. I'm sure more people are interested in doing this swap. As the prices for older maxietorque transmission are ridiculously expensive. 

[Geoff Weeks]

18 minutes ago, Vac-Daddy said:

Started the swap.  My PTO  should bolt right up. i will have to get a different drive shaft. new Eaton Fuller off the shelf in my city, where I live for

You do realize that all 6 bolt and all 8 bolt PTO's are not the same? the input gear on the PTO must match the PTO gear in the transmission and there are 100's of different gears.

I highly doubt the Mack and Eaton share the same pitch gear.

Get with a PTO shop and see if it is cheaper to re-gear yours or start new.

It is highly unlikely that both transmission PTO gears turn at the same speed compared to engine speed.

If your present one is driven off the rear box on the Mack, it will not be anywhere near correct for the front countershaft speed.

[Vac-Daddy]

4 minutes ago, Geoff Weeks said:

You do realize that all 6 bolt and all 8 bolt PTO's are not the same? the input gear on the PTO must match the PTO gear in the transmission and there are 100's of different gears.

I highly doubt the Mack and Eaton share the same pitch gear.

Get with a PTO shop and see if it is cheaper to re-gear yours or start new.

It is highly unlikely that both transmission PTO gears turn at the same speed compared to engine speed.

If your present one is driven off the rear box on the Mack, it will not be anywhere near correct for the front countershaft speed.

You bet, it may need a new PTO. my current mechanic is a transmission and PTO specialist. That's his thing. He told me that's easy, peasy, don't even worry about it. he said finding the proper bellhosing, is probably the hardest part and it took me 3 phone calls.

[Vac-Daddy]

17 hours ago, 67RModel said:

The Mack transmission might seem more expensive than the Eaton on the surface but I can almost guarantee it would be cheaper, all things considered, to just replace what you have. Either by overhaul or just getting a reman unit. Call Weller or similar order exactly what you have delivered to whatever shop you use. Once it gets in they can have it swapped out and everything switched over in a day and you can be back to work the next. Then send your old one back as a core. I would forget about the Eaton in your case.

A remand is 17k plus core of 5k plus shipping and tax of %14 here in Canada, shipped from the USA. New is 25k-30k plus shipping and tax. I already started my swap 🙂 Ended getting an almost new Eaton Fuller for 2k cash, no core. You could order my truck new in 2007 with Maxitorque or Eaton. I found a brand new Eaton to Mack Bell Housing for 800$ cash. Now I only need to sort out my pto and drive shaft. I'm working with a shop who do these swaps quite often. It's really a no brainer. I will keep everybody updated. 

[Vac-Daddy]

On 12/21/2024 at 10:20 AM, Mark T said:

That's another thing that makes me wonder. That's alow mileage chassis. Really shouldn't need a transmission yet. Unless ??? it's had a lifetime of a frustrateed driver (s) trying to get that POS AMI moving.  or  something like that.  Man also asked if the truck was good idea as a foray into self employment.  Tranny is the least of his worries with that one. Even a knowledgeable guy with an equipped shop and a swollew bank account'd have trouble keeping that truck going to be dependable in 2025. Also like Geoff pointed out, stuff you don't think of. Hole in the top cover, PTO(s) alterations to the driveline. Just the transmission swap could blossom into a five digit figure in the blink of an eye. 

Lol ok keyboard warrior. I will keep everybody up to date on the swap. 

[Joey Mack]

Hey bud, is the clutch fork in the wrong hole? Doesnt the cable come off the engine, and pull Forward? Its great that you found the items for a low price. Do you run 2 pto's?

[Vac-Daddy]

On 12/21/2024 at 10:20 AM, Mark T said:

That's another thing that makes me wonder. That's alow mileage chassis. Really shouldn't need a transmission yet. Unless ??? it's had a lifetime of a frustrateed driver (s) trying to get that POS AMI moving.  or  something like that.  Man also asked if the truck was good idea as a foray into self employment.  Tranny is the least of his worries with that one. Even a knowledgeable guy with an equipped shop and a swollew bank account'd have trouble keeping that truck going to be dependable in 2025. Also like Geoff pointed out, stuff you don't think of. Hole in the top cover, PTO(s) alterations to the driveline. Just the transmission swap could blossom into a five digit figure in the blink of an eye. 

A remand is 17k plus core of 5k plus shipping and tax of %14 here in Canada, shipped from the USA. New is 25k-30k plus shipping and tax. I already started my swap 🙂 Ended getting an almost new Eaton Fuller for 2k cash, no core. You could order my truck new in 2007 with Maxitorque or Eaton. I found a brand new Eaton to Mack Bell Housing for 800$ cash. Now I only need to sort out my pto and drive shaft. I'm working with a shop who do these swaps quite often. It's really a no brainer. I will keep everybody updated. Your answer was absolutely no help and a waste of my time reading it, but thank you. Hope you and your family have an amazing Christmas keyboard warrior lol 

[Vac-Daddy]

On 12/21/2024 at 10:09 AM, Joey Mack said:

I too, dont want to be a Dick..  I try to post with an open mind, and i tend to ask questions that I know the answer too, just in case I missed something, or the guy posting may not know what he has..  even though an Eaton will serve him well, and is cheapper to maintain..  Like GW is saying,  there will be a bunch of small's that will cost him time and $$, as well as limited PTO options for him.. That said, with my limited knowledge on swaps and mod's....  I say fix what he has..  it will last a long time as long as it is driven right...  Jojo

A remand is 17k plus core of 5k plus shipping and tax of %14 here in Canada, shipped from the USA. New is 25k-30k plus shipping and tax. I already started my swap 🙂 Ended getting an almost new Eaton Fuller for 2k cash, no core. You could order my truck new in 2007 with Maxitorque or Eaton. I found a brand new Eaton to Mack Bell Housing for 800$ cash. Now I only need to sort out my pto and drive shaft. I'm working with a shop who do these swaps quite often. It's really a no brainer. I will keep everybody updated. Merry christmas! Iwill keep everybody updated 🙂

[Joseph Cummings]

1 hour ago, Vac-Daddy said:

keyboard warrior

WTF?

Dude, you are here with the wrong attitude. Almost everyone here is an old timer with decades of experience. Maybe you need to be on some Billy Big Rigger site 

[Vac-Daddy]

17 minutes ago, Joseph Cummings said:

WTF?

Dude, you are here with the wrong attitude. Almost everyone here is an old timer with decades of experience. Maybe you need to be on some Billy Big Rigger site 

Everybody's been helpful and great. I wished most of them are merry christmas. That one guy, He is a complete jerk off. So, sorry but it's true. 

[67RModel]

5 hours ago, Vac-Daddy said:

A remand is 17k plus core of 5k plus shipping and tax of %14 here in Canada, shipped from the USA. New is 25k-30k plus shipping and tax. I already started my swap 🙂 Ended getting an almost new Eaton Fuller for 2k cash, no core. You could order my truck new in 2007 with Maxitorque or Eaton. I found a brand new Eaton to Mack Bell Housing for 800$ cash. Now I only need to sort out my pto and drive shaft. I'm working with a shop who do these swaps quite often. It's really a no brainer. I will keep everybody updated. 

OK that is insanity lol. Last I saw around here was a Mack reman was around $7500 give or take and an Eaton was $5000 give or take. I have been out of that game for a while though. I would never of thought a reman Mack would be $17,000 but maybe they have just gotten that obsolete over the last few years. I guess if they are 17k up there then you basically have no choice but to do the swap. Based on what you have said it will be way cheaper and in the end you will have a superior transmission. 

[Geoff Weeks]

10 hours ago, Vac-Daddy said:

You bet, it may need a new PTO. my current mechanic is a transmission and PTO specialist. That's his thing. He told me that's easy, peasy, don't even worry about it. he said finding the proper bellhosing, is probably the hardest part and it took me 3 phone calls.

Ok, you don't know how many people I have run into, that say "its a 8 bolt, so will bolt right on" not realizing that every PTO is more or less custom to the application.  Yeah, most Eaton roadranger PTO's will interchange (speed may change some).

If your guy is a PTO specialist, than he will know what is needed.