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HEAVY DUTY MY A**
My vehicle is a 2002 GMC 3/4-ton HD 4x4 Crew Cab 8.1L and Allison trans. At 50K miles a mysterious leak appeared on the transfer case, very small but getting worse. The truck was under extended warranty and the dealer determined the guard for the oil pump failed and allowed the pump to wear a hole in the case. The mechanic at the GM dealership said he had repaired several of this model transfer case with the same problem and that there were no improved parts that would correct this problem. I contacted New Venture Gear and spoke with a gentleman that explained that these failures didn’t occur until “junkyard” mileage and that they didn’t have a solution but were working on it. I’ve spoken to other repair facilities that concurred that this is a common problem that can occur at low miles. My vehicle is used primarily for towing with very little 4x4 use. I would think a vehicle of this type would have a service life of 200K or so without replacing a transfer case housing. Have you heard of other 263 failures and do you have any input on a fix if this occurs again?
Name Withheld, Via e-mail
This one caught me by surprise, but after doing a little investigating, I can say that everything you said appears to be true. The New Venture Gear-263XHD transfer cases, and other similar NV tcases, have been plagued with trouble like this and a lot of owners are unhappy. What happens is that a retainer clip that locates one ear of the oil pump housing in the case breaks and the ears begin rocking around in their slots, eventually wearing a hole in the case and causing the t-case to leak. The warranty fixes range from replacing the case half to installing a blob of JB weld over the outside of the hole... which does nothing to solve the root problem and usually leaks again down the road. My friend at The Diesel Page (www.62-65- dieselpage.com), Jim Bigley, steered me to a company called Merchant Automotive (www.gmdieseltech.com/616- 399-7169). Eric Merchant has been building GM Duramax diesels for years now and has encountered this problem often. Enough times that he developed a fix in the form of a new oil pump housing. It has larger ears than the OE housing. The load is not concentrated on such a small area so the clip doesn’t break, the case doesn’t wear and everybody’s happy. Eric advises that if your case already has a hole worn into it, you are best off to replace the rear case half. Repairing the case properly, he said, often costs about the same as a case half. A few owners have installed the Merchant pump housing as a preventative measure. In that case, Eric advises replacing the retainer spring as well. He also suggests pulling the t-case to do the job properly on the bench. The thing about this problem is that it has nothing to do with using fourwheel drive. The pump is operating in all ranges. Shame on GM and New Venture for letting this problem get out of hand.
AX THE AX-5
I have a 2000 Wrangler with a 2.5L and, from what I’ve read, also has an AX-5 5-speed — which took a dump on me at 80,000 miles. I have found used AX-5s for around $850 with a 30 day warranty. Are there any other options on a small budget. Will the AX-15 work with some mods, or do I just need to suck it up and put in a used or rebuilt AX-5
Heath Frye
York, South Carolina
On a budget, Heath, my advice is to suck it up and find the best deal on a rebuild. The AX-5 as AX-15 trannys do not directly interchange (either at the engine or at the t-case). You could adapt another type of tranny into your Jeep, such as one of those big truck 4-speeds, using bits and pieces from Advance Adapters, but it wouldn’t be cheap or easy. If you go that far, you ought to just swap in a 4.3L V6 with a suitable GM tranny and be done with it. From here on in, do regular oil changes on your AX-5 and no more speed-shifting or “rev-n-dumps” ! Just kidding!
RANGER RALPHED
I have a ’94 Ranger with the 5- speed, 4.0L and Borg Warner 1345 manual shift transfer case. I lifted this truck 8-inches and am running 35 inch tires with limited slips and 4.56s front and rear. As soon as I put in the 4.56 gears and the limited slip in front, it gutted the transfer case. I would like to beef this weak link and hear a lot about the Atlas but wow, the price is really high. What do you think my best option is to fix this t-case issue?
Mike Lamfers
Windsor, Colorado
I’m not so sure it’s a transfer case issue at all, Mike. Hear me out. You didn’t give me much info on exactly how the t-case failed. It coulda just been it’s time to go to the big Coors can factory in the sky, maybe from all that great ‘wheeling in Colorado.... which I miss daily. The Borg Warner is really not a terrible transfer case, especially with stock engine power in front of it. I know of many that handle V8 power with no serious trouble. I think you may have other demons at work here and so I’m going to give you a couple of things to look at before you spend big money on something new... and by the way, a limited slip up front should have no effect on a transfer case. Driveshaft problems with an 8-inch lift, however could be an issue.. Maybe you have a shaft that’s binding at full droop, a slip yoke that’s too short and bottoming out on axle uptravel, or maybe you have some vibration issues? The other thing, and don’t take this the wrong way because I just got a letter about it, maybe you don’t really have 4.56 gears at both ends. I have a letter from a poor guy that had gears installed in a Chevy and the shop put 4.88s in one end and 4.10s in the other! He didn’t grenade the t-case, a miracle in itself, but he didn’t find out he had a problem until after hitting the trail. Even on dirt it wasn’t terribly apparent until he crawled some rock. At that point, it became a Yeeha moment. Anyway, my opinion is that your Ranger’s Borg Warner should serve you well, and if it doesn’t, it’s most likely due to outside factors.
ZEBRA ROMEO TWO
I have a 2000 Chevy S-10 with the ZR- 2 offroad package. It has the 4.3L Vortec and an automatic transmission. I would like more power and better fuel economy. I have looked at installing a throttle body spacer and considered a Brute Force cold air induction kit but I have a K&N air filter already. I would also like to know if drilling holes in the airbox lid would do anything but cause headaches.
Brian Buchanan
Via e-mail
I think you are working at the wrong end of your truck. If you do one or the other, you’ll usually get more benefit from a free flow exhaust than a freeflow intake. Until you increase the engine’s air requirements in a major way with a camshaft change, major EFI reprogramming, head porting, or extending the rpm range, etc, the engine can’t use any more air flow capacity. With a really restrictive intake system (which the Vortec does not have) a free flow intake can reduce pumping losses (the ability to inhale without restriction, which costs some horsepower) at lower speeds and that can be worth some power. Pumping losses from intake restrictions just aren’t much of an issue for modern trucks. There is usually more exhaust restriction than intake, especially since you have a free-flow air filter in there already. Go with a free flow exhaust for your first money spent and if you do it about the time your OE exhaust is ready to die, it’s a cost effective change. Don’t expect any major mileage or power increases, but a little of both will be there. As to holes in your airbox, I say nay. What will happen is that the engine will then be sucking hot underhood air rather than cooler outside air and that will cost you power and maybe some mileage. Stick with your ducted air intake to reap the benefits of cooler air. Installing a cold air intake after the exhaust system is installed would be your next option.
CLASSIC BRONCO LOCKUP
I have a ’71 Bronco and want to put a locker in the front end. I have a Dana 30 in it now but have a used Dana 44 that needs gears, bearings, seals and all four ball joints. Would it be OK to put a locker in the Dana 30 or better to spend more money on the Dana 44. I have 4.11 gears and run 32 inch tires.
Marvin Brandt
Hazelhurst, Wisconsin,
If your Dana 44 was out of an early Bronco, it’s not a huge increase in beef over the D30. Sure, it has a bigger ring gear and perhaps a stronger housing (2.75-inch tubes vs 2.50 but both were .031-inch wall HREW tubes) but in terms of the weakest link, they both have the small 260 size u-joints. That’s one item that can be upgraded in both axles by using alloy shafts set up for the bigger 297/760 size u-joints. Given that your 44 needs so much work and you are running only 32s, I’d stick with the D30. That said, I think I’d drop down from a locker to a limited slip until you get the weak axle/u-joint situation improved. A true locker will put a lot of stress on those u-joints. The limited slip will give you a lot of extra traction up front without too much binding that breaks parts. If you have plans to go to bigger tires, then bite the bullet and opt to build the Dana 44.