Blazin Trail-Shafts
Question: I have a '93 S-10 Blazer four-door. It has a 350 with a 700R4 and the stock 236c transfer case. I have an HP44 front and a 14-bolt rear. I just bought an HP60 for the front and thought while I'm at it I should beef up my front driveshaft. Does anyone make a 1350 or bigger yoke that will fit the front output of my transfer case? I want something stronger than those little baby U-joints that GM put in there, but I don't really want to get away from the pushbutton 4x4.
Jason
via 4wheeloffroad.com
Answer: The NV236 transfer case is the same basic case as an NV233 part-time transfer case, except it has Autotrac or full-time four-wheel drive. When the Autotrac button is pushed, the Transfer Case Control Module (TCCM) locks the front axle, and monitors the front and rear transfer-case outputs for speed. When it sees the rear speed increase, it applies an internal clutch to lock the front driveshaft to the rear. Although it is not locked in, these cases always rotate the front driveshaft, even in 2WD.
The early version (like the one in your question) uses a front U-joint just like a NV231. Flanges from an NV231 will interchange, although sometimes the seal has to be changed. The production U-joint is a 1310 series. In 1997 the front output was changed to a male spline, and a CV was installed in the front driveshaft. These units need to use the flange developed by Diversified Creations (810.227.4777, www.diversifiedcreations.com) to install a standard U-joint. Then you simply need a companion flange for your larger 1350 U-joint, and most driveshaft shops, such as Tom Woods Custom Drive Shafts (877.497.4238, www.4xshaft.com), can supply this.
Toy trouble
Question: I have broken the motor mounts in my '85 Toyota truck. It has a 22RE, dual cases, and 5.29 gears. Are any better versions available?
Dustin G.
via 4wheeloffroad.com
Answer: Funny you should ask. I recently had the same problem with my '86 Toyota mini-truck. I contacted the folks at Rockstomper (www.rockstomper.com) and they sent me some of their fabricated mounts, which worked flawlessly while I was out wheeling. My truck has a late-model four-cylinder swapped in, but it uses the same style mount as a 22RE, but with a longer stud than normal for the aluminum engine brackets. Rockstomper has the motor mounts you are looking for.
'Cage Cube?
Question: I was wondering about the pros and cons of building a rollcage of square or rectangular tubing versus round tubing. I worked at Caterpillar, and all of their equipment uses square rollcages, and the prices seem much cheaper to do so. Any help would be appreciated.
Gregg P
via 4wheeloffroad.com
Answer: The rule of rollcages is that it matters more how you build it than what you build it with. Square tube isn't a bad choice, but there are some issues with working with square tube. It is heavier for a given size since it actually has more surface. It's also harder to work with since you can't bend it as easily as round. However, square tube is a lot stronger if you're using it as a beam.
Anther problem is that there is a far greater range of material quality in round mechanical tubing than you find in square tube. They don't make DOM or 4130 square tube, or at least it's not anywhere near as easy to find. All your common square sections are HREW and may not even be held to as tight a spec as round HREW tube as far as material quality, wall thickness, and construction quality go.
I've contacted some engineers, and they also noted that when you're loading any structural member as a beam, you figure the vertical leg height as your primary factor in strength. A square tube will have two totally vertical "legs" that are the full height of the tube. A round tube will have a mathematical average of the round section that gives you an equivalent vertical "leg." The square section's "leg" is always way more since all the material is oriented in the correct direction.
If you have tight-fitting joints, solid-quality welds, and a design that utilizes triangles to disperse forces, then using square tube isn't a bad choice. In fact the biggest reason square or rectangular tubing isn't used for rollcages is because round tube just looks better.