Question about thermodyne transmissions

[Vladislav]

Water manifold on your engine (as I expect by the look of the engine) must be a very common part used on many Mack engines of 70's, 80's, 90's and even 2000's years. It's cast iron, consists of two portions, front and rear. I may be having some extras besides my personal needs but you may be lucky finding it in your home country too. Very similar manifolds (or even the same) were used on E7 and E-tech Mack engines mounted on Renault Magnum trucks. Yes, similarity of some Mack engine parts spreads from late 30's up to 2000's years!

But also depending on the kind of the issue with the manifold it could be fixed. If there's a crack it can be cooper-soldered or welded or just epoxy-glued for some limited service time (a decade or two )

[mowerman]

Well, there’s plenty of parts around for those things. Good luck.

[mowerman]

Meant used engine parts lots of them 

[mrsmackpaul]

On 2/7/2026 at 12:44 AM, Brocky said:

The Mack engineers designed the complete power train to accept the heaviest (and overweight) loads that a customer could put on the truck. As a hobby truck, bobtailing or with a light load of toys, this usage of the entire available power train is not necessary. I would first determine what YOU are going to use the truck for?? If NO heavy work is planned, you can play with the present duplex and enjoy yourself, with out going to the work and expense of swapping transmissions.

My brother bought a ex Australian Army Mack, 285 Maxidyne 5 speed

Anyway, bro bought this truck and reckoned a 5 speed was no good and needed extra gears like a 12 speed

I said 2 him, just let it lug, and when you wanna change a gear don't, let it lug a lot more  

Once you've done this for 6 months, see if you really want a 12 speed 

That was a few years ago now and the 5 speed is still there 

My point is just get it going, drive it for a while and then see what you think

 

Paul