Are premier GP-38 and GP-40 same size

Pugsly,

I'm sure you'll get some good answers here, but a quick look underneath says yes. Where you need to watch out is the smoke unit connection. Make sure the smoke funnel thingy lines up. Also, they should both be the same series e.g. PS 2 or PS 3.

Hm.  In "real life," a GP38 is non-turbocharged and has two exhaust stacks.  A GP40 IS turbocharged and has a single stack.  So if MTH was trying to be prototypical, they would have to have different smoke units.

I'm 95% sure that in real life, both rode on the same size frames and were similar in most dimensions.  The main difference is that some RRs wanted a low-maintenance workhorse, and others needed the extra horsepower that came with the turbo.

Pugsly,

I assume you are inquiring about PS3 locos. I've  had them both apart at separate times. The 2 smoke stacks on the 38 are twinned together inside with a plastic duct to a common smoke unit that has is single output. If they line up, you have a fair chance. I'll watch tomorrow and see what other answers you get. I don't mind taking them apart and sending you pics if need be.

I can tell you that the sound will be very different. The 38s are throaty and fun to listen to, IMO. The 40s is just a whine at any speed, and my least favorite locos to run because of that (or even to buy). Boring! You may be able to change the sound file  but that is uncharted territory for me.....

99% sure I put a mth gp40 shell on a gp38-2 mth frame and had to accommodate the rear screw holes that did not line up.

Also, the GP38s have 2 exhaust stacks; GP40s only one.

Inquiring because I have a non powered gp 40 and (pan am gp-40).  And am trying to power it and can get a cheap ps2 gp 38.   Can’t find a reasonably priced ps3 gp 40.  Don’t really care about accurate prototypical sound

@Pugsly14 posted:

Inquiring because I have a non powered gp 40 and (pan am gp-40).  And am trying to power it and can get a cheap ps2 gp 38.   Can’t find a reasonably priced ps3 gp 40.  Don’t really care about accurate prototypical sound

Aha! In my limited experience, not counting screw holes, the way the lighting gets powered is different between PS2 and 3. Attached is a picture of PS2 shells that use spring contacts that rub against foil plates on the PS2 chassis to power lighting. I believe PS3 locos use 2-pin connectors directly to one of the boards.

The yellow arrow is pointing to the smoke duct used in a 38 to get single-sourced smoke distributed to the 2 outlets.

On the pic showing a PS3-40 and a PS2-38 side-by-side, showing the location of the smoke units in relation to the outlets. Rolled up, I think the short answer is you'd be signing up for a ton of work. Hope this helps!!

BTW...I'm a Pan Am groupie as well!

Bob

Thanks!!!!   Some very good info.    

You're welcome!

As as a side barb, that MEC 260 is a new old stock shell I found on eB. Then I bought a PS2 with black running gear to install it on. I feel your pain because all-in, I have $600 in it, but it has the most amazing sound of anything I own. I then went one to replicate that in a an MEC 251, again with another sacrificial PS2 to install it on.  Together, they put on a good show! The only thing I have left to do is repaint the steps.