In The News Trip Reports Features Land Use Doh! Photo Album Cover Shots
Project Vehicles Product Reviews Quick Looks Wrenching Featured Vehicles YJ FAQ Calculators
BC 4x4 Suppliers 4x4 Suppliers For Sale Ads Wanted Ads
Coming Events Links Message Board Mailing List


Project YJ - tera Locker vs. Lockright
Introduction
Installation
Test Drive
Conclusion

 
 

 
 
Project YJ Articles
Introduction
Detailed History
Rubicon Express
Spring-Over
Bumper/Tire Rack
Rhino Liner
Scout Axle Swap
Detroit Lockers
vs. Lockrights
TeraLow Dana 300 4:1 Kit
Go 2 Twister Dana 300 Re-Indexer
Bestop Supertop
Transmission Overhaul
TJ Flares Install
Rocker Armour
Bestop TrailMax Aqua Sport Seats
Kilby Gas Tank Skid Plate
Teraflex Revolvers
Kilby High Volume Automatic Transmission Pan
Hi-Steer Conversion

 
 

Installation

Tera Low parts The kit comes with these parts:
  1. All new replacement seals.
  2. All new replacement gaskets.
  3. Rear output shift rod (modified to clear the larger 4:1 intermediate gear).
  4. Two sliding drive gears (more on this later).
  5. Intermediate gear.
  6. Front output gear.
  7. Input gear.

Now, about those two sliding drive gears. The original versions of the Low300 kit did not include these gears. They re-used the stock gears. The kit now comes as a complete, five-gear set to meet the demands of larger engines. Increased detent pockets on the shift rail help prevent popping out of gear in two low with twin stick applications. This has been a common problem with stock Dana 300 cases and twin-stick kits so it is nice to see Tera Mfg. address this issue.

The original sliding drive gear is on the left. The new TeraLow gear is on the right. The new gear is cut slightly differently to reduce backlash and should better withstand the added torque of V8 motors. The red circle is highlighting the wide clearance notch in the TeraLow shifting rod. This is required to accomodate the much wider diameter of the 4:1 intermediate gear. The original rod is outside of the case.

A competent home mechanic could install this kit but we opted to use Jason Conover who has installed several Tera Low kits. Jason began the install by cleaning the new parts in parts washer to remove the waxy, protective coating used during shipping. Meanwhile, I removed disconnected the shifter linkage, driveshafts, breather hose and speedo cable from the transfer case.

With the case removed from the Jeep and on the bench, Jason started cleaning the exterior before commencing with its disassembly. Disassembling the case is a bit like working with a puzzle. The sequence is important, especially if you're planning on putting it back together again. It's recommended to use a Dana 300 service manual or take detailed notes during the disassembly.

Removing some of the components required a specific sequence. If you don't have a manual, be prepared to do some headscratching during dis-assembly. Here you can see a comparison of the stock (left) and TeraLow (right) intermediate and input/ouput gears.

Once the case was emptied of its internals, Jason used an angle grinder to notch a portion of the access opening on the bottom of the case. This was necessary so that the much wider 4:1 intermediate gear could be installed. With that done, the case was cleaned out and re-assembly began. This process was the reverse of dis-assembly except that he replaced the output shift rod, the intermediate gear, the sliding drive gears and input and front output gears with the 4:1 replacements. The new seals & gaskets were also used. If you're unsure of the condition of your transfer case, you might want to order Tera Mfg.'s Dana 300 overhaul kit as well. This kit comes with the bearings & seals needed to completely overhaul the Dana 300. It also includes an intermediate shaft, a shim set for bearing adjustment and a shift fork friction pad set. Project YJ's case was in excellent condition so we left it as is.

The larger diameter of the TeraLow intermediate gear required notching the access opening. The re-assembled case (we just have to bolt on the access cover plate).


 
 
 

Previous | Menu |  Next
BC4x4 Main Page
Click to Send Email
to BC4x4
(20-sec delay)
SEARCH
ARTICLES
In The News
Trip Reports
Features
Land Use
Doh!
Photo Album
Cover Shots
TECH
Project Vehicles
Product Reviews
Quick Looks
Wrenching
Featured Vehicles
YJ FAQ
Calculators
MARKETPLACE
BC4x4 Suppliers
4x4 Suppliers
Message Board
FOR SALE Ads
WANTED Ads
RESOURCES
Coming Events
Links
Message Board
BC4x4 Mailing Lists

Except where otherwise noted, all contents on this site are Copyright 1999 - 2009 © 599244 BC Ltd. All rights reserved. No content on this site may be reproduced without express permission from 599244 BC Ltd.
Disclaimer: Activities and vehicle modifications appearing or described on this website and its pages may be potentially dangerous. We do not endorse any such activity for others or recommend it to any particular person - we simply describe our experiences and opinions. If you choose to engage in these activities, it is by your own free will and at your own volition. Use common sense and remember that none of this material is presented as being recommended by a professional mechanic or driving instructor. This information is presented for your amusement only. Do not take unwise risks, consult a certified professional if you are not sure of something. - 599244 BC Ltd. (bc4x4.com) and the authors of these articles assume no liability for how any particular individual chooses to use the information presented here.