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PA Performance 120 Amp High Output Alternator (87-90 2.5L or 4.2L Jeep Wrangler YJ)

Item J102468
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Market Price $153.99 You Save 22% ($34.29)
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$119.70 (each)

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      Product Information

      Features, Description, Reviews, Q&A, Specs & Installation


      • 100% New Upgrade Alternator
      • Includes Manufacturer One Year Warranty
      • High Output - Increases Charging Capacity
      • 60 Amps at Idle - 120 Amps at Maximum
      • Natural Cast Finish
      • Includes 6 Groove Serpentine Pulley
      • Requires Power Wire Upgrade
      • Fits 1987-1990 Jeep Wrangler 2.5L & 4.2L YJ Models


      More Power. Upgrade to the 120 Amp PA Performance Jeep Alternator. This YJ alternator is a brand new upgraded replacement, not re-manufactured like other companies sell and is tested at the time of assembly for complete reliability. It comes with internal voltage regulator and a 6 groove serpentine pulley. The 120 Amp alternator will increase the charging capacity at all RPM Ranges and produces 60+ amps at idle and 120+ amps at maximum .

      Peace of Mind. Why waste your time and money rebuilding your alternator over and over when it will only fail, replace it with a brand new high performance alternator that includes a Limited Lifetime Warranty directly from PA Performance for peace of mind.

      Application. The PA Performance Alternator is an upgraded replacement to be installed on 1987 to 1990 Jeep Wrangler YJ models equipped with a 2.5L or 4.2L engine. This alternator requires an upgraded output wire (4 gauge or larger) and at least 175A fuse protection for installation.

      Fitment: 1987 1988 1989 1990 Details

      MPN# 1798H

      CA Residents: WARNING: Cancer and Reproductive Harm -


      Customer Reviews (4)

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      Ratings Summary

      4.5 out of 5 overall rating from 4 customers

      • November 19, 2019

        4 1989 Wrangler - Bekman

        Unit came set up for serpentine belt and required the use of the old v-belt pully and spacers (not certain that the alignment is 100). Also new part has no provision for the back mount. Of course I added a second wire of the same gauge parallel to the original harness for the power to the distribution block. Functionally it is fine, just be prepared for the minor modifications.

        Helpful (2)
      • March 12, 2019

        4 1989 Wrangler - BobB

        120 amp alt install

        The alternator is a little smaller and little lighter than the stock one. I have A C on my YJ and it is easier to remove and put back on because the stock alternator is bigger and you to have to take the lower slide bracket off because of my dryer for the A C is on the mounted on the fender well, the new alt. you do not have to remove the bracket just slide to the rest position and remove. My problem is the new alt. does not line up with serpentine belt I had to shim the alt. pulley out about a 1/8 of an inch to get it to line up. I also added a bigger wire from the alt. to the battery along with the stock one everything works good.

        Helpful (3)
      • March 17, 2017

        5 1987 Wrangler - LloydC

        So far, so good

        Everything I needed was included with the alternator, with the exception of a larger ring terminal to make the connection to the existing wiring. The alternator came with a 6 groove serpentine belt pulley installed, but the v-belt pulley was included and only took a minute to swap out. Total installation time was about an hour, mostly because I had to find my package of larger ring terminals.

        Helpful (17)
      • March 08, 2017

        5 1988 Wrangler - Kaitlyn

        Great upgrade

        I purchased this alternator to upgrade from the stock 94 amp. My Jeep Wrangler YJ has factory a/c and the previous owner put the wrong alternator in, he replaced it with the 78 amp one. I noticed quite a difference in the charging and now when I have my headlights and radio on, my volt meter doesn't drop! Very happy with this alternator!

        Helpful (17)

      Questions & Answers (2 answers)

      2 Top Rated Questions

      The information notes the need to install a 175 amp fuse link . Is that supposed to be added to the new output wire? Does the electrical conversion plug as shown Pictured come with the alternator ? Thanks

      • Yes, that conversion plug should come with the alternator, and you would wire that in to the new output wire.

      Helpful (0)

      Does the upgraded output wire come with this alternator ??

      • This does not include the upgraded output wire.

      Helpful (0)
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      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Alternator

      Will It Fit My Wrangler

      • YJ Wrangler 2 Door - 87, 88, 89, 90

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