Hummer H1 Parts and Accessories

1998 Hummer Model Year Changes.
With major changes for '97 and '97.5 there were relatively few changes for 1998. Several changes were made towards quieter operation, differential gear ratios were changed so engine revs would be lower at highway speed, geared hubs were made quieter , the cooling fan and clutch were changed and an insulated top was added for Open Top Models. Although all these items help make the 1998 quieter, the difference over the 1997 model is not dramatic. Two new colors were added for 1998, Candy Apple Red, which replaced Gloss Red, proved very popular and Competition Yellow which replaced the harder to match Fly Yellow of 1997.

Powertrain and Identification Information.

  • VIN 10th Digit designating year = "W"
  • Engine: 6.5L Diesel 170 H.P. 290 lb. ft. VIN 4th digit ="Y" 36 produced.
  • Optional Engine: 6.5L Turbo Diesel 195 H.P. 430 lb. ft. VIN 4th digit ="Z" 909 produced.
  • 4L80E Electronic 4 speed Automatic Transmission. VIN 5th digit ="A"
  • Top Speed 83+ mph with Turbo.
  • 945 '98 models built.
Significant changes for 1998.
  • Axle ratio changed from 2.73:1 to 2.56:1 on Turbo Diesel Models lowering engine revs at highway speeds. Non-turbo models remained at 2.73:1.
  • Rear cargo doors added to central locking system.
  • Cam style camber adjustment early running change. Before cam adjusters, Hummer alignments were done by the dealer in the first 1,000 miles after delivery. With the cam adjusters initial alignments were done at the factory. New cam adjusters make alignments easier but are easier to knock out of spec. Some Hummer owners who use their Hummers off-road have retrofitted the earlier style shim adjusters.
  • New insulated top on Open Top Models.
  • New finishing on geared hubs to make them quieter.
  • New fan clutch comes on at higher temperature and new 8 blade cooling fan offers quieter operation. VIN 180123 and above.
  • New Color Candy Apple Red replaces Gloss Red.
  • New Color Competition Yellow replaces Fly Yellow.
  • Burgundy Metallic no longer available.
Valuable upgrades to look for in a '98.
  • Although steering components were upgraded several times by '98, the factory "Problem Solver" Idler and Pitman arms introduced in later years are much more durable than those on a '98.
  • Enhanced engine block- Turbo Diesel Engines with block castings before May 1999 are susceptible to #8 cylinder cracks. Most frequently the first symptom of a cylinder crack is coolant being forced out of the cooling system causing the "check coolant" light to illuminate. Many engines have been replaced with blocks of the same design. Even though the enhanced blocks were first produced in May 1999 it took some time before they made their way through the system and into Hummers as either original equipment or for replacement. Even Hummers produced in 2000 are likely to have the pre-May 1999 block casting. There is a casting number on the right rear of the block under the cylinder head which should be E_99 (May 1999) or later. Unfortunately the codes changed through the years so identifying the enhanced blocks is even more difficult. Later blocks also use metric bolts to attach the bell housing but it is unclear whether this clearly identifies an enhanced block. Although enhanced blocks were installed in Hummers produced before the engine manufacturer change to General Engine Products (GEP), the easiest way to make sure a Hummer left the factory with an enhanced block is to check the 4th digit of the VIN on 2001 and later 6.5L turbo diesels. If the 4th digit is an "F" the engine was produced by GEP and is sure to have the enhanced block from the factory.

'98 Specifications, options & Prices:
Available colors:
Competition Yellow. New Color for '98
Candy Apple Red. New Color for '98
Green Metallic. (G10)
White. (W8)
Silver Metallic. (S15)
Bright White. (W14)
Black. (B9)
Although most factory custom colors show up on emergency vehicles and as factory tests, custom colors were available on all Hummers for an additional $1,000 charge. Below is an example of a Hummer with a factory experimental color, Cactus Green. Cactus Green never made it into full production.
Body Styles Available in '98:
HMCS. 4-Passenger Wagon. VIN 6th & 7th Digits "84" HMC4. 4-Passenger Hard Top. VIN 6th & 7th Digits "83"
HMCO. 4-Passenger Full Door Open Top. VIN 6th & 7th Digits "90" XLC2. 2-Passenger Hard Top Enlarged Cab. VIN 6th & 7th Digits "89"
TOTAL PRODUCTION COUNT BY MODEL AND COLOR. "X" Colors are "Experimental" or special order, often seen as production colors in later years.
COLOR
FULL DOOR OPEN TOP (HMCO)
WAGON (HMCS)
HARD TOP (HMC4)
2-PASS. ENLARGED CAB (XLC2)
TOTAL
B9 (Gloss Black)
74
136
40
8
258
G10 (Gloss Green)
26
54
17
1
98
R19 (Candy Apple Red)
62
92
17
2
173
S15 (Silver)
22
56
11
89
W14 (Bright White)
29
68
17
16
130
W8 (Gloss White)
38
24
7
7
76
Y18 (Fly Yellow)
2
2
4
Y20 (Competition Yellow)
53
27
11
1
92
X02 (Safety Green)
1
1
X06 (Chrome Yellow)
2
2
X13 (Bright Green)
1
1
X17 (Smokey Carmel (Mesa Dusk))
1
1
2
X19 (Military Style Green)
2
2
X20 (Gloss Red R7)
4
8
12
X21 (Safety Green)
1
1
X22 (Brilliant Blue)
1
1
X24 (Tan)
1
1
X26 (Dark Slate (Nightstorm))
1
1
X27 (Deep Amethyst)
1
1
Tan Interior
144
179
49
372
Gray Interior
163
286
78
46
573
Cloth
271
435
109
12
827
Vinyl
36
30
18
34
118
Deluxe Trim
307
465
127
33
932
Fleet Trim
13
13
NA Diesel
24
4
8
36
Turbo Diesel
253
423
112
36
824
Turbo Diesel (CA)
30
42
11
2
85
TOTAL
307
465
124
46
945

Adventure Accessories
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