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New Member
Hello i am Ryan the son of a veteran model railroader who was born into the hobby. Anyway I thought about the crazy idea of converting my dad's 1st generation Athearn Genesis SD70 into a hybrid of either an Atlas or a Kato by changing the gears and possibly the motor to make the old beauty sound as good as it looks which is arguably in some ways better than some of my dad's Katos and Atlas'. My dad was very dissappointed when he first got the genesis expecting it to sound alot better but instead sounded like the typical Athearn which is said by alot to not run the greatest. My dad thinks this project is too hard and borderline impossible but I am alot more optimistic. My question is to all of you is can this be done before I decide to tear the beauty apart and if this "extreme kitbashing project" (as I like to call it) has ever been done I'd like to see some resources on how to do it.


Been Nothin' Since Frisco
You might just try replacing the trucks. SD70Ms and SD75Ms from the first release were known to have warped trucks, which can cause tracking issues as well as binding within the truck. That could be the source of the noise.

I got lucky - the first run SD75Ms I have do not have this issue and run fine. As far as motor/gear noise is concerned, they don't sound as quiet as Kato diesels, but they're pretty darn close.

You might try this link:

The item is shown out of stock now, but is expected soon. Alternately, you could write Athearn describing the problem and they might send replacement parts free of charge. I received replacement handrails for my SD75Ms when I asked if they had replacement sets I could buy since mine were warped and suffered from shrinkage during the casting process.


New Member
Unfortunatly I think the problem is farther than just the trucks but I'll tell my dad that thanks. My prediction is its just the Athearn growl but my goal with this project was to make it sound as good as the best Athearn (sound wise) my dad's got which he got an amazing deal for (15 bucks if you can believe it) I might just do what you said and replace the trucks and give it a grease job but I have my doubts of course that it'll sound any good. Still I'd like to try out this project and see how it goes to me it seems really interesting afterall my dad was able to get a Stewart Hobbies with a Kato drive that just sounded awful when he first bought it from the train store many years ago which I believe the guy at the train store said would never sound like the true Kato that it was ever but my dad kept plugging away at it and eventually got it to sound absolutely quiet (couldnt get it any more).
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Diesel Detail Freak
I'd suggest the new trucks and a Motor from A-line/PPW. My lone experience with a PPW engine is perfection, though it'll and up being wired up like an old Blue Box unit thats been DCC'd.


New Member
Thank you so much hopefully my dad will be pleased with the outcome. :) Now I just have one question which PPW motor would be the best to put in the SD70 Athearn Genesis so that it'll run smoothly?


Diesel Detail Freak
I'm betting that 70321 would fit, if you're iffy, drop down to 80321 which fits BB GP's.

Here's a copy of their motor specs chart, should you decide to re-use the Genesis fly wheels (which might be smart) {L/W/H in MM}:
Item #  Length  Width  	Height  Speed (rpm)  	Current (ma)  	Shaft (mm)
40321 	 33 	 18 	23 	8,500 	 	90 	 	2.0
40322 	 24 	 18 	23 	9,200 	 	80 	 	2.0
40323 	 20 	 12 	14 	17,000 	 	50 	 	1.5
40324 	 30 	 13 	16 	11,000 	 	70 	 	2.0
30321 	 40 	 29 	-- 	3,700 	 	48 	 	3.0

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