Thanks for the information on FP7s, number of cars in passenger trains, & power supply.
  I'm finding that, when the locomotive has plenty of power, the weak links are some of the couplers.  Last night, I had to move a Bachmann boxcar with truck-mounted couplers from the front of the train to near the back so that it had less weight to pull.  It was okay until I tried putting a hill under my track.   

Guilford Guy,
I coupled my milk tank car to my F7B.  What does FP7 mean, passenger?

Yampa Bob,
I did read your thread on measurements of power use.  I don't have any gauges for measuring power usage.  I can turn off the sound with EZ Command but I don't know how I could turn it off on DC.  My Bachmann & Intermountain locomotives came with little or no specifications, other than a manual from the maker of the sound system.  These items are expensive enough to rate more information to be included with them.
I already ordered the 5 amp booster for EZ Command, because some have said that 2 DCC with sound locos are too much for the 1 amp power supply.  I could not avoid getting my F7B unit with sound, if I wanted a DCC match for my Intermountain F7A.  Sometime, I'd like to add sound to my Spectrum EMD SD45, which would mean running 3 sound locos simultaneously.  I really like hearing the UP's horn when it passes north of town several times day & night.
  The Intermountain F7A & B I ran separately on a DC track only 1 on the track at a time, after I'd initially run them on the DCC track.  I did not push them; they just would not move until I turned the 7VA DC power pack's throttle to about 2/3 (My cheap F7 DC raced around the track).  They run much better on DCC power.  The SD45 now pulls 19 cars fast enough for me, about 80+ HO mph.  I just wonder why the F7A & B aren't as fast.  If their DCC sound drains power from their speed, then I hope the power booster will speed them up.  If a passenger train is supposed to be faster than a freight train, I'd like mine to be so.

 How many amps is your larger power supply?

 Back in the '50s & '60s, it was fun to see what different railway's cars were in a GN train.  I wish I could remember more of them, but I've included DM&IR iron ore cars, a SOO Line boxcar & a Burlington Northern coal car in my Great Northern train.  Sometime, I may find pictures of GN freight trains from that era, showing the different names.

 Congratulations on your birthday & your supportive wife!  My wife bought me my first HO train as an early 64th birthday gift about 2 months ago.  She takes an interest in each new package that arrives with another addition.

Yampa Bob,
Yes, I'm a nightowl & suffer from insomnia--except after supper. 
  I tried my Intermountain F7A & B on DC.  They wouldn't even start until I turned the throttle almost to maximum!  At max, their horns sounded but they didn't move.  After they got going, they would run at max & about 3/4 & 2/3 speed.  Running them very slowly seems not possible.
  model-city now has EZ Command 5 amp booster for $130--about half the list price, so I took the plunge.
  pdlethbridge, right, I don't want to have to clean the gears, as someone was advised to do here after using 3in1 oil!

Yampa Bob,
  Thanks for the advice on lubrication & the estimates.  I wondered when Jim Banner said that the EZ Command is 1.5 amps but the manual says 1 amp.  You explained the discrepancy.  My SD-45 is pulling 18 cars.   The EZ Command 5 amp power booster is so expensive that one could buy a Digitrax Zephyr for less, although it is just 2.5 amps.  I am wondering which would be the better investment.

  Yes, I have a 39' layout for the passenger train.  I just got a Sheffield Farms milk tank car, because my grandfather Sheffield had a dairy farm.  The information with it says that milk tank cars were coupled to passenger trains, because passenger trains were faster.  The milk was chilled before loading into these unrefrigerated cars.  However, my Intermountain F7A-B DCC\with sound passenger locomotive is not as fast as my Spectrum EMD SD-45 DCC\without sound freight locomotive.

Jayl1 & ajp3751,
Thanks for the helpful information!  One of these days, I'm going to be there with my camera when the Union Pacific that passes here (Menomonie, WI) several times a day & night, crosses north of town.  Maybe, it's one of those models.

   Can anyone tell me the respective eras of & differences between these locomotives:  Bachmann HO 60301 RTR GP40 w/ DCC  Bachmann HO 60904 RTR SD40-2 w/ DCC?  Bachmann is offering attractive prices on both models.

  It would be helpful if manufacturers of locomotives included information about maintenance, including lubrication.  Is there a site on the web that shows what parts to lubricate & when to use oil & when grease?  Somewhere, I read that manufacturers often lubricate their locomotives too much.  I haven't found any oil coming off my models onto my fingers, though.

Jayl1 & Nigel,
Thanks for the advice.  I guess 10 minutes wasn't long enough for breaking in a locomotive.
  Is LaBelle a thicker lubricant than the Wahl clipper oil many have recommended for retarding oxidation on the rails?

 I just got the F7B DCC/Sound unit for my Intermountain F7A DCC\Sound Great Northern.  Using the instructions from Bachmann EZ Command Control's DVD, I had no problem re-programming it from Address 3 to the Address 1 for my locomotive.  I have yet to measure whether or not the B unit increases the speed of my passenger train.  Initially, running it & my Spectrum EMD SD-45 freight train slowed the freight, but, after a while, it re-gained some speed.  I still run the 8-car passenger train at full throttle & the 18-car freight at 3/4 throttle to keep them at about equal speed.
  I had to resort again to wiring 4 cars together, because the McHenry 52 couplers I used to replace horn & hook on my IHC cars don't seem to close as securely as some knuckle couplers.
Reading The Great Northern Railway: a History, I learned that the new Empire Builder of 1947 had 12 passenger cars.  I have 8.  Twelve 11" long passenger cars, plus the F7A & B, would make a train about 12' long, occupying almost a third of my 39' layout.  I'd like to hear from anyone on this forum who runs a passenger train on a home layout.  One option would be to use 72' cars, instead of 85' ones.  Online sellers often don't state the length of their passenger cars, however.

 I did replace the horn & hook couplers on my 6 IHC passenger cars with McHenry 52 couplers.  That seems to be working.  I also replaced a defective coupler on the rear of my Spectrum EMD SD-45 with a Kadee 5 metal magnetic coupler.  I found that Bachmann uses whisker couplers in their SD-45.  Now, I can run my locomotive frontwards again to pull the train.  It is pulling my 18 freight cars without straining.
  The Life-Like horn & hook couplers on the cars from my initial train set hold pretty well to the knuckle couplers on other cars.  I find that some cars hold better when I move them to a different part of the train.

  Thanks, Jhanecker2 & Yampa Bob, for dissuading me from the folly of trying to remove the doors!
    After painting over the NASCAR logos on 4 boxcars from my initial train set, I placed Great Northern decals on them.  The tiny bits with microscopic print are difficult to manipulate.