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The Preventive Maintenance Magazine
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HMMWV: LED Light Kit
| July 11, 2022
Operators, did you know that there’s a LED light kit available for your HMMWVs? You heard correctly! Get an LED light kit with NSN 5945-01-564-0484. The kit includes front and rear light assemblies parts list and...
Be Prepared for Hot Weather: A List of Must-Read PS Articles
| June 21, 2022
Soldiers, even though it happens every year, it somehow seems to sneak up on us. It’s summer and the heat is on! Read on to see how to keep you and your equipment cool...
Ground Vehicles: Drive Like Your Life Depends on It!
| June 10, 2022
Warfighters, MSG Half-Mast requests you huddle up with your fellow Soldiers and remind them that driving tactical vehicles is serious business. Just how serious is it? Find out here...
HMMWV: New Winter Tire Assembly
| June 8, 2022
Warfighters, a few months ago we let you know the Army was testing the KO2 winter tires. They have a three-peak mountain snowflake (3PMSF) rating, which means they’re considered severe-snow-service-rated. Here's the scoop...
Up-Armored HMMWV: Inspect Seat Belt Assemblies
| March 17, 2022
Maintenance leaders, TACOM Safety of Use (SOU) message 22-002 advises you to inspect the seat belt assemblies (both lap and shoulder seat belts) in your up-armored HMMWVs. Here's why...
M1151A1 HMMWV: Ordering the Engine Compartment Hood
| March 16, 2022
Dear Half-Mast, I’m trying to replace a broken engine compartment hood on an M1151A1 HMMWV. However, NSN 2510-01-432-3338 shows the hood as AAC V in FED LOG. That means it’s a terminal item. Can my unit still order the...
Tactical Vehicles: Don’t Make Winter Driving a Chilling Experience
| Feb. 28, 2022
Operators, winter driving presents unique challenges. The bottom line is that you need to be prepared for these challenges. Here's what you need to know...
HMMWV: PMCS Procedures Streamlined
| Feb. 2, 2022
Here’s some good news, operators! According to TACOM Maintenance Information Message (MIM) 22-011, PMCS procedures have been streamlined for your HMMWVs. This means you’ll spend less time getting ready for missions because...
HMMWV: Winter Tires
| Jan. 26, 2022
Warfighters, you may have heard the Army is testing a new winter tire for HMMWVs: the KO2. KO2 winter tires have a three-peak mountain snowflake (3PMSF) rating, which means they’re considered severe snow service-rated. Read...
MRAP: Learn Your Rollover Lesson
| Jan. 21, 2022
This article initially appeared in PS 771 (Feb 17), p. 11. Operators, it’s always better to avoid a rollover than to experience one. Remember these lessons learned before you start the day’s mission. Get the lessons here...
Tactical Vehicles: 2021 Year-in-Review
| Jan. 21, 2022
Maintenance leaders, NSNs were the most frequent topics covered in 2021 for tactical vehicles and trailers. Corrosion prevention and the roll-out of Non-Combat Operations Maintenance Plan (NCOMP) were also hot topics this...
HMMWV: NSN for ABS Brake Fluid
| Jan. 5, 2022
Warfighters, if you only need to order small amounts of DOT 5.1 brake fluid for your HMMWV’s ABS system, you’re in luck! Read on and we'll tell you what you need to know...
Up-Armored HMMWV: NSN for Flap Assembly
| Dec. 28, 2021
Some units have received the wrong part for the HMMWV flap assembly when ordering NSN 5325-01-628-4842. The part is shown as Item 17 in Fig 405 of TM 9-2320-387-13&P (Mar 21). Here's what to do if that happens to you...
Up-Armored HMWWV: B-Kit Heated Windshield Accessory Kit
| Oct. 20, 2021
You might have seen the June 2020 PS Magazine article about the up-armored HMMWV converting the front windshield from improved vehicle emergency egress (IVEE) glass to rigid glass. We told you that units must order a B-kit...
HMMWV: Driver Training and Safety
| Oct. 20, 2021
Listen up, drivers! The added weight of your up-armored HMMWV protects you during combat. But it also makes your vehicle handle a lot differently than a non-armored HMMWV...
HMMWV: New Articulating Tow Bar
| Sept. 24, 2021
Soldiers, the Army has a new light articulating tow bar (ATB) that allows you to assemble and connect the tow bar to your HMMWV while the vehicle is shut down and in park. The ATB weighs only 69 pounds and provides a 2:1...
HMMWV: AFES System TM Updates
| Sept. 10, 2021
Serious injuries or even fatalities can occur if the proper procedures for the automatic fire extinguishing system (AFES) and manual fire extinguishing system (MFES) aren’t followed...
M997A3 HMMWV Ambulance: New and Improved HVAC Kit on the Way
| Aug. 5, 2021
Soldiers, excited about receiving the M997A3 HMMWV ambulance with the new and improved heating, ventilation and air conditioning (HVAC) system kit?...
HMMWV: Ordering Steering Gear
| Aug. 3, 2021
Dear Half Mast, my unit has been trying to order a steering gear (also known as the pitman arm) for an M1097R1 HMMWV that still has the older steering box and system. FED LOG lists an acquisition advice code (AAC) of X...
HMMWV: TCM Has Replaced EPROM
| July 7, 2021
Mechanics, make a note that the erasable programmable read only memory (EPROM) has been replaced by the one-piece transmission control module (TCM), which is needed to operate your unit’s HMMWVs...
HMMWV: Air Conditioning Re-Charge Tools
| June 21, 2021
Mechanics, is it time to re-charge the air conditioning in your unit’s HMMWVs? Be sure to use the right NSN when ordering the refrigeration tool kit...
HMMWV: Wiper Assembly Bracket
| May 27, 2021
Mechanics, ever get frustrated when you’re replacing the wiper assembly on your M1151A1 or M1151A2 HMMWV because the bracket is straight while the wiper motor assembly is angled? Don't fret. Here's the solution...
Up-armored HMMWV: Authorized Alternators
| May 26, 2021
The 210-amp alternator, NSN 2920-01-598-4541, is standard issue for all up-armored HMMWVs. The 200-amp alternator, NSN 2920-01-420-9968, is a terminal item, but it can still be ordered and used until all stock is...
FMTVs, HMMWVs: Summer Swelter? A/C to the Rescue!
| May 18, 2021
This article initially appeared in PS 801 (Aug 19), p. 14-15. Summer temps demand a lot from vehicle air conditioning systems, especially up-armored FMTVs. To get the most out of your FMTV A/C, keep it charged to the right...
HMMWV: Use Gun Weapon Mounts Only on M1151s
| April 29, 2021
Only use gun weapon mounts on M1151-series trucks. That’s the dedicated HMMWV weapons carrier...
HMMWV: Battery Disconnect Switch Optional
| April 14, 2021
Dear Half Mast, A lot of shops in my unit aren’t in favor of installing the battery disconnect switch for the M1165A1 HMMWV because it’s an accessory kit and not a mandatory item. Is there an MWO that authorizes using the...
M997A3 HMMWV: Fan Speed Knob NSN
| April 5, 2021
Dear Half-Mast, I’m having trouble finding an NSN for the fan speed knob and switch in the back of the M997A3 HMMWV that controls how fast the fan blows. Can you help?...
HMMWV: Don’t Overfill Fuel Tank
| March 25, 2021
Some Soldiers are overfilling their HMMWV’s fuel tank, causing fuel to leak from the top of the tank. Don’t overfill the fuel tank! Read on to find out why...
HMMWV: Facts on Fording
| March 24, 2021
Dear Half Mast, I’m looking for the maximum allowable flow rate of a water crossing for HMMWVs. Can you help? Certainly. But first, I need to clarify the wording of your query...
HMMWV: Non-Combat Operations Maintenance Plan
| March 22, 2021
Soldiers, are you maintaining HMMWVs that aren’t being used as much as before? The Non-Combat Operations Maintenance Plan (NCOMP) will better align maintenance requirements to actual usage of HMMWVs rather than time-based...
Tactical Wheeled-Vehicles: Safe Slave Starting
| March 16, 2021
This article initially appeared in PS 720 (Nov 12), p. 11-12. Combining weak batteries with freezing temperatures won’t exactly give your vehicle the best environment for starting. But with the right help, you can get it...
M1097R1 HMMWV: Order Transmissions by Serial Number
| Feb. 4, 2021
If your unit has the M1097R1 HMMWV, NSN 2320-01-346-9317, with a retrofitted engine, check the serial number before ordering a new transmission for the vehicle...
HMMWV: Preparing for Winter Driving
| Dec. 8, 2020
A properly maintained and safely driven HMMWV is your first line of defense in cold weather. But freezing temperatures add another layer to already tough conditions...
HMMWV: Lower Front Ball Joint Mounting Bolts
| Dec. 3, 2020
Dear Half-Mast, I’ve been working on an M1097R1 HMMWV for my unit. I noticed that outer cap screws are installed from the top down and inner cap screws are installed from the bottom up just on the lower front ball joint...I'm...
HMMWV: Transmission Failure Fix
| Nov. 30, 2020
Dear Half Mast, The unit I’m with has eight (8) M1165 HMMWVs. The transmissions are completely burned out in five (5) of the vehicles after only being driven 300 miles annually. Are there any updates or known issues with...
HMMWV: Fuel Tank Straps and Bolts
| Nov. 30, 2020
Maintainers, does the spacing between the fuel tank straps on your HMMWVs have you scratching your head? If so, you’ve likely noticed differences between the spacing on your truck and what’s prescribed in TM 9-2320-387-13&P...
HMMWV: Turn Signal Switch LED Light
| Oct. 29, 2020
Mechanics, have you tried installing the new LED headlight kit on your HMMWVs and noticed the only way the turn signal works is with the bulb taken out of the turn signal switch? That’s because there’s a problem that prevents...
M1151A1 HMMWV: A/C Hose Orders
| Oct. 22, 2020
Soldiers, if you’re having trouble ordering an air conditioning hose, NSN 4720-01-656-9748, for the M1151A1 HMMWV, there’s a reason why...
HMMWV: Taking Measures to Reduce the Risk of Rollover Accidents
| Oct. 15, 2020
Soldiers, HMMWV rollover accidents happen, but you can decrease the likelihood by taking the steps outlined in this article...
Joint Battle Command Platform (JBC-P): Equipment Transfer Guidance
| Sept. 24, 2020
When changing from the M997A2 to the new M997A3 armored HMMWV ambulance, unit maintainers need to take specific steps to maintain a fully-functional Joint Battle Command Platform (JBC-P) digital computer set. Instructions are...
DCGS-A: New TGS TM Makes Tactical Touchdown
| Sept. 14, 2020
TM 11-5865-1098-10 (Jul 20) is the new operator’s manual for the Tactical Intelligence Ground Station (TGS) AN/TSQ-179E (V) 2, NSN 5865-01-673-1760. The HMMWV-mounted system is part of the Distributed Common Ground...
Up-armored HMMWV: ABS/ESC Maintenance Info
| July 28, 2020
Up-armored HMMWV (UAH) vehicles with antilock braking system/electronic stability control (ABS/ESC) were fielded in 2019. ABS/ESC makes your unit’s HMMWVs safer, enhances handling during emergency braking and reduces the risk...
HMMWV: Troop Seat Interface Kit Canvas NSN Update
| July 27, 2020
A unit recently searched IETM 9-2320-387-24P (Mar 14) for the canvas piece that’s part of the troop seat interface kit. But when they ordered NSN 5325-01-628-4842 shown as Item 17 of Fig 405, only the hook and loop fastener...
Up-armored HMMWV: IVEE Windshield NSN Replacement
| June 30, 2020
The up-armored HMMWV’s improved vehicle emergency egress (IVEE) left-hand windshield, NSN 2541-01-560-7677, and right-hand windshield, NSN 2541-01-560-7680, have been canceled by TACOM...
M997A3 HMMWV: Serpentine Belt NSN
| June 25, 2020
Dear Half-Mast, I need a serpentine belt for the engine in my M997A3 HMMWV ambulance but can’t find the NSN. Can you help me out?... ...
HMMWV: Kinks Offer Hose Protection
| May 11, 2020
Dear Half-Mast, I’m trying to find an NSN for the metal cover designed to protect the upper radiator hose from damage by the generator belts. But I’ve had no luck finding it in the IETM, TM 9-2320-280-13&P. Can you help?...
HMMWV: Slave Start = Smart Start
| Feb. 5, 2020
This article initially appeared in Issue PS 804, pages 10 - 12.Dead HMMWV batteries? Think twice before you grab that handy ground power unit (GPU) for a jump start! The ONLY approved method to jump start a HMMWV is with a...
Parts List Correction
| July 22, 2019
TACOM has determined that Items 6 through 15 in Fig 209 of TM 9-2320-387-13&P in IETM EM 0323 (Mar 14) aren’t in synch with the figure call-outs. An updated parts list is forthcoming. Keep reading to learn more...