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![1-Wire Mini GM Alternator [12 Volt, 120 AMP]](https://www.jegs.com/images/mini_750/500/555/555-10138.jpg)
Vehicle Info NeededJEGSPART NUMBER: 555-10138
1-Wire Mini GM Alternator [12 Volt, 120 AMP]
$22799$246.99You Save$19.00
4 left in stock
Ships on Oct 26, 2026
Lowest Price Guarantee1-Wire Mini GM Alternator12 Volt 120 Amp 1-Wire Hook-Up Single One Groove V-Belt Pulley 6.125 in. Bolt Hole Spacing Center to Center Cast Aluminum Case Natural Finish
Please take a look at this dimension chart 
JEGS 555-10138 1-Wire GM Mini Alternator Features:
- GM CS121 Style
- 12 Volt 1-Wire Hook-Up
- M6-1.0 Positive Terminal Stud with 10 mm Hex Nut
- Internal Regulator
- 120 Amp Output
- Excellent Output at Idle
- Compact Size Fits into a 5 in. x 5 in. Space
- To Achieve Optimum Output, Alternator Case Grounding is Recommended
- Optional Ground Strap or Support Bracket Mounting Location on the Back Side with M8-1.25 Thread
- M8-1.25 Mounting Boss Thread
- Includes (1) M8-1.25 x 31 Mounting Bolt
JEGS 555-10138 1-Wire GM Mini Alternator Note:
- This Mini Alternator is equipped with a factory-style OE GM 4-pin plug that is covered with a plastic cap. Removal of the cap will allow the use of a factory GM 4-pin connection if so desired.
Easy Hook-Up GM Mini 1-Wire Alternators
JEGS Mini 1-wire GM Alternators offer additional clearance and weight savings over full-size alternators with the same charging output. Features an internal regulator. Easily installed by connecting 1-wire from the alternator to the positive side of the battery. Requires use of appropriate low mount-alternator bracket (sold separately). Note: Low mount units will not clear stock front crossmember, steering and sway bar due to below crank centerline positioning. Check for potential clearance issues before ordering.
Part TypeAlternator
Product LineJEGS 1-Wire Mini GM Alternators
BrandJEGS
Package Height7.0
Package Width7.2
Package Length7.8
Weight10.0 PG
Part CategoryPerformance Parts
Voltage Compatibility12
One-Wire CapableYes
Pulley IncludedYes
Pulley Belt TypeV-Belt
Alternator Brackets IncludedNo
Pulley StyleV-Belt Pulley
Advertised Amperage Output120 amps
Regulator IncludedYes
Alternator Case StyleGM CS121
New Or RemanufacturedNew
Amperage Rating120
One Wire CapableYes
Alternator FinishNatural
Belt IncludedNO
Part FitmentSemi Universal
Regulator StyleInternal
Pulley Groove Quantity1
Package Qty1
Package TypeEA
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