M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

1952 - 1968, M38A1, M170, questions, discussions, regarding anything related to the M38a1 series.
Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Mon Apr 08, 2019 9:08 am

You are correct.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO


Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Tue Apr 09, 2019 4:28 am

1955 era CJ-5 evolved from the 1952 era M-38A1. There are some appendages from the M-38A1 design that are evident onCJ-5. The recessed bow Sockets, the cut out on the Hood for the Snorkel, Permanently attached blank battery box cover on cowl, small mirror mount pad on cowl. Recess around Fuel tank filler, and a handfull of other appendages.
Very few 1955-1971 CJ-5's used the 7.00-16 NDT Tire option, most had 7.60-15 GoodYear Suburbanites, 7.00-15 (All Service) NDT's or 6.00-16 GoodYear NDT's. There was even a 9.00-13 option for the CJ-5.
A nice feature on the CJ-5's of the 50's was the comfortable bucket seats, the driver's seat had 3 positions that required unbolting it.
The CJ-5 4 Cyl used the same steering ratio as MB thru the CJ2A/CJ-3B, M-38A1 had a different steering ratio.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Tue Apr 09, 2019 2:10 pm

The M-38A1 has Safety Valves on top of the rear axle tubes adjacent to the backing plates that prevent excess lubricant pressures from occuring at the rear wheel bearings. The CJ-5's (and CJ-2A, CJ-3A, CJ-3B and CJ-5 with similar Semi Floating Rear Axles) only had vent holes with no fittings. The grease inside the vent hole sealed out dirt and water which makes it very important to grease these vents per factory schedule.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Sat Oct 05, 2019 4:36 am

Just a reminder, the rear wheel bearings are a much ignored lubrication item
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Mon Oct 12, 2020 2:41 pm

Just another reminder, those two vents on your M-38/M-38A1 are important enough to deserve TLC-Do not over grease or you will create a lot of work for tools you will not have but will need. This is what the Army trained M-38/M-38A1 Jeep Mechanics for because they had over a hundred thousand of them.
I were a M-38/M38 Mechanic once. :wink:
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Thu Oct 22, 2020 1:20 pm

Too bad Willys did not adopt the M-38A1 Heater on the 50's-60's 4 Cyl CJ-5's.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Thu Oct 22, 2020 1:24 pm

Do not use the M-38A1 Parking Brake to slow the Jeep Down. The External Contracting/Internal Expanding Parking Brake can lock the driveshaft and flip the Jeep.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

JMZ421
G-First Lieutenant
G-First Lieutenant
Posts: 646
Joined: Sat Jun 02, 2012 1:21 pm
Location: N.E. Ohio

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by JMZ421 » Fri Oct 23, 2020 9:41 am

Thanks for the reminders, John

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Sun Mar 21, 2021 5:59 am

Early M-38A1's (thru early 53) were factory equipped with the CUNO Oil Filter
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Sun Mar 21, 2021 6:16 am

And you do know that you can remove the gas tank to rid the leaves, dirt, etc. and spot paint to control rust.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Sun Mar 21, 2021 9:38 am

Anyone use "Strip Calk" to seal the various floor panels and Fenders to body? CJ-5 also used it. Early M-38A1 (52-53) used "Anti Squeak" like on MB prior to changing to "Strip Calk". Strip Calk and Scotch Calk are available from local Auto Paint suppliers. They are identical, use the dark color if you have a choice. The color of this product is similar to cloths line rope gray.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

User avatar
USASA
Sergeant Major of the Gee
Sergeant Major of the Gee
Posts: 309
Joined: Thu Jul 28, 2005 4:44 pm
Location: Houston, TX

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by USASA » Fri Mar 26, 2021 9:58 am

Yes. I used the 3M strip caulk when putting everything back together. Worked quite well and - 600+ miles later - is holding up nicely with no panel squeaks.
Gene
'54 M38A1
'67 M416

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Fri Mar 26, 2021 3:14 pm

Good man, you are welcome in my motor pool any time.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: M-38A1 QUIZ-HOW WELL DO YOU KNOW THE M-38A1?

Post by Joe Gopan » Thu Jul 08, 2021 1:48 pm

Servicing these vents on schedule is very important.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO


Post Reply

Return to “M38a1 Technical Knowledge Base”

Who is online

Users browsing this forum: No registered users and 31 guests