There comes a time when the Factory battery is down for the count and the replacement options start to come up. In my case the previous owner opted to to replace the 100’s battery with the same size (group 27F) Les Schwab special. Probably not a bad way to go for my 100’s former life as a mall cruiser.  A short 3 years after the Xtreme Power battery found a home in my cruiser, it was already on it’s way to where batteries go to die.

I feel like the factory sized group 27F battery specs can be improved upon so I set out to put in the biggest, meanest battery I could. I have previously installed a group 34 DieHard Platinum as an Auxiliary battery using Slee Offroad’s 2nd Battery Tray and liked the result so I thought another DieHard Platinum would be the ticket. Sears has a group 31 marine battery that has the stuff – 1150 CCA with 205 minute reserve. The model PM-1 (group 31) is a battery of AGM design (like the group 34 I have) which is vibration resistant making it a great choice for offroad and manufactured by Odyssey – considered to be the preeminent maker of automotive batteries.

I have previously shoehorned a group 31 battery in an LX470 and adapted the factory battery clamp to work, but I always felt it was a little half baked. Several members of iH8MUD had done similar installations – one member even created a custom clamp and sold a few to members. Though that members efforts to make a clamp were well received, he wasn’t able to continue production.

Fast forward a hand full of months and Slee Offroad has developed not only a clamp for a group 31 battery, but a matching tray as well. The Slee Offroad Battery Tray and Clamp kit replaces the factory battery tray and clamp. It was designed to fit the exact DieHard PM-1 battery I wanted to use. The Slee kit is supplied complete with hardware, rubber isolation strips and terminal stud converter to allow for direct fitment of this battery to factory vehicle terminals. Slee coats the tray and clamp in PolyArmor coating, that provides excellent corrosion protection and also resitant to chemicals.

The Slee Offroad group 31 Battery Kit includes the following:

• Battery Tray
• Battery Clamp
• Aluminum Spacers
• Button Head Allen Bolts, washers and nylock nuts
• 40″ Adhesive padding
• Battery post adapter for positive sub-post
• Detailed instructions

My Install also included these additional items.

• VTE Battery Terminal Covers (466N9V02 Red / 466N9V14 Black)
• Mil Spec Terminals (Napa Auto)
• Custom Fuseable Link Extension (copper bar)

Installation of the Slee kit is very straight forward. This process took me one hour. This is a simplified overview – you should follow Slee’s included instructions.

1. Remove the factory battery clamp and retain the J-Bolt and 12mm head bolt.
2. Disconnect and remove the existing battery.
3. Remove the factory battery tray (pops out of retaining holes / no fasteners). Discard.
4. Inside the drivers side front wheel well locate the washer reservoir shroud (it’s black).
5. Remove the 3 (10mm) head bolts and remove the shroud (keep the bolts and shroud).
6. Next you’ll need to enlarge the three holes where your factory battery tray used to live. In my case I only had to enlarge one closest to the headlamp. I used some sealer to keep any potential rust out of my newly enlarged hole.
7. Cut two strips of the supplied adhesive matching the long side of the battery tray and stick them.
8. Position Aluminum Spacers and set the new Slee battery tray in position.
9. Insert new bolts through the tray, spacers and through body holes.
10. On the bottom side of the body (DS inner fender) you’ll see the bolts coming through, attach a washer and Nylock nut to each.
11. Using a 7/32 Allen wrench and 14mm open end wrench tighten all nuts securely.
12. Reinstall the washer reservoir shroud with the 3 (10mm) bolts you removed earlier.
13. Cut additional sections of the supplied adhesive to fit the new Slee clamp.
14. Position the J-Hook bolt on the new Slee clamp.
15. Install new DieHard PM-1 battery into Slee tray.
16. Position Slee clamp to insert J-Hook bolt into the Land Cruiser body.
17. Position Slee clamp over battery and adjust positioning and adjust j-Hook bolt nuts for proper fit.
18. Secure leading edge of Slee clamp with 1 (12mm) bolt (from factory clamp) to the body.
19. Install battery post adapter on battery smaller post – this allows the factory fuseable link to reach the positive post closest to the engine. In my install I have an extension so It was not necessary to use the battery’s sub post with the adapter.
20. Connect positive terminal to battery sub-post. Connect negative terminal to battery main-post.

For my version of the installation I have mil-spec terminals on my leads with some additional accessories wired to them so I used a piece of copper, twisted and slotted as a link extension (see images below). My main Ground terminal from the engine block was slightly short, so I terminated it to the sub-post while my mil-spec negative terminal connects to the main-post.

Overall this kit is extremely well made and finished. I suspect it will have no problem living as long as the Land Cruiser and beyond. Installation is direct and can be done by a less experienced / home mechanic. If I have to pick nits, it would be the inclusion of SAE hardware instead of Metric – small nit, but I was slightly annoyed. Also, some of the very first kits were shipped with an error in the instructions indicating to discard the washer reservoir shroud – don’t. According to Slee, only a few kits shipped out with the errored instructions and all current shipping kits have been updated.