Grouchy Granny Tranny
Question: I have an SM465 four-speed manual transmission in my '90 Chevy truck. The darn thing keeps hopping out of Third gear when under load! Is this something I can fix, or does the transmission need to be replaced? I used to love the transmission, but after the long years of abuse it seems tired and I'm getting frustrated.
Paul
via 4wheeloffroad.com
Answer: I feel your pain, as I have the same problem in one of my trucks. Novak Adapters (877.602.1500, www.novak-adapt.com) has both an SM465 rebuild kit and a new Third gear upgrade kit. The upgrade kit comes with beveled clutch teeth to help lock it in place under load. Novak sees this problem in one out of every 20 SM465s and can supply both the kit and the gear upgrade for under $300. The best part is that Novak has seen many customers rebuild it themselves with just basic tools, snap-ring pliers, a bearing puller, and a press.
More Granny Tranny Queries
Question: I would really like some info on swapping out a SM465 four-speed tranny for a TH350 automatic for my '81 Chevy 4x4, which has a 400ci small-block. What all would I need to do the job completely, and where's the best place to find transmission and parts new and used?
Lisa Jo
via 4wheeloffroad.com
Answer: The switch to a manual is threefold. For starters, you'll need the transmission, bellhousing, clutch, flywheel, and adapters to your transfer case. These can be had from Novak Adapters (877.602.1500, www.novak-adapt.com) and Advance Adapters (800.350.2223, www.advanceadapters.com).
Then you'll need the pedal assembly and clutch master and slave cylinder assembly. The pedals should come from a truck of the same era. The master and slave cylinder come from later-'80s, early-'90s GM trucks, but are dependent on what bellhousing you use.
Then you will likely need to move your transmission crossmember and run new driveshafts since the SM465 is shorter than your TH-350. For a similar install search for "1986 chevy 1-ton five-speed manual transmission swap" at 4wheeloffroad.com.
Lifting A Long Jeep
Question: I am the owner of a '05 Jeep Rubicon Unlimited. I was researching 4- to 6-inch lift kits for my Jeep. I talked to two lift kit manufacturers, and one said there is a difference in ordering between a TJ and my LJ. Another company said there is no difference and that a TJ lift would bolt right into a LJ. I was wanting your unbiased answer. What is the difference, if there is one?
J.W.
via 4wheeloffroad.com
Answer: For the most part, the suspension will be the same. However, the spring rates should be different for the longer Jeep Unlimited due to the greater weight. (Did you know that although many people call the TJ Unlimited "LJ," it was never named so by Chrysler or Jeep? Chrysler referred to both models as the TJ, but LJ for "Long Jeep" caught on with the public.)
Also, if you go with a long-arm suspension, there will likely be a difference between the TJ and the LJ because of the longer wheelbase, though this could depend on the links or the mounting plates. I think I would recommend a long-arm suspension for that much lift; so yes, there should be a difference between a TJ and an LJ.
Nuts, I'm Confused
Simple CJ
Question: I have an '85 CJ-7 that I have been rebuilding from the frame up into a trail-ready Jeep that I can use for years and pass down to my 2-year-old son. I am keeping the 258 and five-speed but upgrading the axles to the Wrangler JK Mopar Rubicon 44s front and rear. I sandblasted the frame, painted it with POR 15, and mounted 21/2-inch Skyjacker leaf springs with Confer shackles, and now I am trying to mount the new axles. I have cut off all the mounting hardware that come on the 44s so I can weld on the new leaf spring perches.
The problem I have is with the front axle and mounting the perches. The driver-side perch is now lining up on the diff housing. If I mount to the housing I have no way of getting a U-bolt around the inside of the leaf spring to the axle. If I mount the perches to the housing I would have to raise the perches to avoid notching the housing gussets, which would lower the front end about an inch, causing me to use an add-a-leaf to level the Jeep, right? Or do I move the leaves to outside the framerails and box out new spring mounts? I plan on doing some moderate to difficult trails but still want to be able to drive on the road. I plan on running 35s or 37s and upgrading the gears to 4:88 later on.
The next question I have is about the transfer case. Now that I am running a driver-side pinion I need to flip the transfer case. Do I go with the STaK housing and gear to 4:1 with a heavy-duty output shaft, or do I spent the extra bucks and drop in an Atlas? I figure the Atlas will cost me an additional $500 but with a lot less time in switching my Dana 300 guts to the STaK housing.
My goal with using these new 44s is to keep the Jeep simple and use parts that will be available years down the road (axleshafts, brakes, engine parts).
Brandon J.
via 4wheeloffroad.com
Answer: Sounds like a great project! Those new Mopar Wrangler JK axles are a great upgrade for any Jeep project, and I think the easiest way to swap them in your Jeep is with a full-width conversion kit from Blue Torch Fab (205.521.7333, www.bluetorchfab.com). This will put the springs outboard and make mounting springs to your axle much easier.
Your transfer case dilemma is tough. I've never had anything but great performance from the Atlas transfer cases I have used, but the $500 you would save could be applied to the full-width kit from Blue Torch. I like the STaK products but have never used one of its Dana 300 flip kits personally, so I guess I would lean toward the Atlas if you can afford it.
I like your questions because you have the right idea: plan your vehicle out, use as many off-the-shelf parts as possible, and build something to last as a family heirloom. I'm giving you this month's Nuts, I'm Confused award, a set of Corbeau Baja Suspension Seats (801.255.3737, www.corbeau.com) for your buildup. We have some of these in our old Tacoma project truck, and they are great off road, hold up well in open-weather vehicles, and have enough side bolstering to hold you in place without feeling cramped. The seats are made with a tubular frame covered in fabric or vinyl and are set up to accept three-, four-, and five-point harnesses. The suspension system in the seat it made of nylon and military-grade cord to support your torso doing rough wheeling at various speeds. The seat can be ordered in a variety of colors and should be perfect for your buildup project.