4x4 AnswerMan – Truck and SUV Off-Road Tech and Maintenance

Feb. 25, 2013 By Jaime Hernandez
Chevy Truck 4x4 working the red rock in Moab, UT.

Have a truck or SUV question for the 4x4 AnswerMan? Send your questions to editor@off-road.com. Please include your name and location, and be as detailed as possible about your questions.

More 4x4 AnswerMan Columns

January 2013

December 2012

November 2012

TOYOTA PICKUP RING & PINION INSTALLED INTO FJ80 AXLES
Hello 4x4 AnswerMan,

Is the Toyota 4x4 truck front axle ring and pinion gear the same as the FJ80 front axle ring and pinion? My friend wants to take a Toyota 4x4 truck front axle ring and pinion and put it into my FJ80 front axle. Will this work?

Thanks,
Dom

Toyota High Pinion 80-Series Land Cruiser 3rd Member from JT

Hi Dom,

Your friend has good intentions, but it won’t work. The Toyota Land Cruiser axle uses a high pinion 3rd member. The gears are different; Toyota pickup front axles typically have a centered pinion. The high pinion design on your FJ80 3rd member is much stronger than the Toyota straight axle Hilux/pick-up. It also has more clearance and will provide a better angle for the driveshaft.

Your best bet is to simply buy a set of Toyota 8" Reverse Cut Ring & Pinion Differential Gears for your FJ80 front axle. 

Good luck!

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HUMMER LEVELING TORSION KEYS
4x4 AnswerMan,

I was planning on leveling my H3 and was looking for a kit. Early in the article it said "The advantage to using leveling torsion keys from ReadyLift is they are specifically designed to provide up to a 2.25-inch lift without affecting the factory ride." Later in article it said "On the road it drives fine, but off-road it is a bit more bouncy. It takes getting used to, but that’s the case with any lifted vehicle, especially one with torsion bars that have been cranked." My question, is there an advantage using a kit over turning the factory keys?
Thanks, Stephen M.

Letter sparked by ReadyLift Hummer H3 Leveling Kit Review

 

Hi Stephen,

The higher you lift/crank the torsion bars on a GM IFS suspension, the stiffer the ride. Brian, owner of the H3, had to take it back and have them drop it down to about 2 inches of lift in order to get a smooth ride again. It's possible that during the initial installation the torsion bars were over cranked, past the 2.25-inch limit recommended by the manufacturer (more like 2.5 to 2.75 inches), making the H3 bouncy.

The benefit to the ReadyLift torsion leveling keys is being able to get more lift without over cranking the torsion bars. You might be able to get some additional lift with stock ones, but not as much as with these specially engineered leveling keys--if you want to continue to have a smooth ride. 

Good luck!

ReadyLift suspension leveling torsion key (left), Factory Hummer H3 torsion key (right).

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LIFTING MY SILVERADO
4x4 AnswerMan,
 
I'm trying to lift my 2006 Silverado with a 6-inch suspension lift. I've heard I'll blow a hub bearing doing that though after about 8,000 miles. Is there any way I can avoid this?  I've heard something about dropping my transfer case but I don't know too much about it. Hoping you can help me.  Thanks, AJ W.


Hi AJ,

Lifting a vehicle does alter suspension geometry, but it should not have any impact on the wheel bearing or wheel hub. What will impact your wheel bearings’ life are the large tires you might be adding to compliment the lift. It really comes down to how hard you wheel the truck. If you daily drive it, and sometimes play in the dirt, then it can last you thousands of miles. Now if you beat and bash on it every weekend, then it will very likely need some frequent TLC.

As far as transfer case drop downs, if you are buying a 6-inch suspension kit from a reputable company, most of the time they will come with these pieces as part of the kit to correct driveline angle. If not, you should be able to source transfer case drop down spacers from your local off-road shop or online.

Transfer Case Drop Down Spacers from Skyjacker


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LIFT & 35s FOR MY SILVERADO
Hi 4x4 AnswerMan,
My name is Garrett. I’m from Katy, Texas. I have a 2008 Chevy Silverado LT crew cab 4x4 5.3L V8. I currently have a 2.5-inch leveling kit installed on my truck. If I get a 4-inch suspension lift can I fit 35-inch tires on my truck?

Garrett L.

Hi Garrett,

If you swap out the leveling kit on your Chevy Silverado with a bonafide 4-inch suspension lift, then you should be able to run 35-inch tires. The only thing to watch is your wheel backspacing. The person or off-road shop installing the lift should be able to give you some options, including wheel spacers or aftermarket wheels if you need them. You can also check with the manufacturer, as they should know if aftermarket wheels will be needed to accommodate these larger 35-inch tires.

Good luck!

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BILSTEIN SHOCKS PART# FOR TOYOTA TACOMA PRERUNNER & 4WD
4x4 AnswerMan,
 I have a 2000 Toyota Tacoma 4x4 TRD.  What Blistein shocks should I use (part#'s)?
Nick

Letter sparked by Toyota Tacoma Off-Road Tune-up Project

Hi Nick,

Here are the part numbers you’ll need.  These are intended for factory height trucks (not lifted).

Front: F4-B46-2284-H1

Left rear: F4-B46-2285-H0
Right rear: F4-B46-2286-H0

*Optional Front leveling RCD/Bilstein (0 - 2.5 inches) Shocks: BE5-D558-T0

These are all available at Off Road Warehouse:
http://offroadwarehouse.com/

Bilstein/RCD front leveling shock for 1st Gen. Toyota Tacoma PreRunner/4WD (top), Factory TRD Tokiko front shocks (bottom).

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FORD F250 5.4 TRITON 4WD
4x4 AnswerMan,

I have a Ford F250 4-wheel drive with 5-speed manual trans and 5.4 Triton V8.  My question is “what can I do to change the gears that are so low you have to go thru all your gears to reach a speed of 50 without nearly pegging the tach?"

Rhonda A.


Hi Rhonda,

One trick on these trucks is to start off in 2nd gear. First gear is really low and will definitely feel like the engine is running away. Only try to use first if you have a heavy load or are starting up a hill. 

Aside from that, some other things that may be impacting the “pick-up and go” are the tire size and differential gear ratio. If you are running really low gears on the differentials, then the only way to fix that would be to get higher gearing that would be more friendly on the highway. You may even need to revert back to stock, depending on tire size.

My suggestion is to check out Randy’s Ring & Pinion website for more information on gear ratio, transmission ratio and RPM:  http://www.ringpinion.com/Calc_GR.aspx

Feel free to give them a call. I’m sure they’d be happy to help you with your high RPM problem.

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WIDE TIRES ON MY FORD F150
4x4 AnswerMan,

Hi I'm Austin. I have a 95 F150 4x4 XLT w/ the 302. I currently have 31x10.50x15s on it, and I don’t want to buy new rims. Would 33x12.50x15s fit without rubbing, and if so would a leveling kit stop it from doing that?

Austin M.

Hi Austin,

There are a combination of things you can do to help with clearance issues when running these wider off-road tires. First, wheel spacers may be in order to move the tires away from the frame and prevent excessive rubbing. Second, if you start having rubbing issues with the bumper or fender, you can either lift it a little or simply trim off some of the sheet metal with a saw-saw or cutting wheel. If you don’t like the cut finish, you can add some fender flares, likes these ones from Bushwacker.

Happy trimming!

Related article:
Project Trail Bronco: Bushwacker Dura-Flex Flare Review

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4X4 SNORKEL & EXHAUST MODS

Some good questions were brought up in our D-I-Y Custom Snorkel article about what happens if water gets in the snorkel and exhaust back pressure created from submerging the vehicle?

A little moisture in the intake can actually be good and help increase horsepower in the engine. A bucket full of water in the snorkel could be detrimental, including the possibility of hydro lock. As a safety feature, most snorkels have a low point that collects water, and this can be at the air box. That said, you always run the risk of not being cautious when water fording. 

As for engine backpressure from a submerged exhaust, if your vehicle is spending that much time in deep water or lumpy mud bogs, adding a snorkel exhaust to match your intake might be in order. Something that comes up above your truck’s bed or cab roofline, similar to exhaust systems used by the military, would solve that problem. 

Military Humvee featuring a snorkel intake and snorkel exhaust system.

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LIMITED SLIP FRONT END
4x4 AnswerMan,  It [the differential decoder] said I have limited slip, but if I have it in the rear, do I have it in the front too?
 Cliff Jones

Letter sparked by our Toyota Differential Decoder

Hi Cliff,

The factory Toyota front axle on pickups did not come with a front limited slip differential (LSD). Now somebody may have done some hocus pocus in there and put one in. According to some Toyota gearheads, the factory Toyota Supra rear 7.5" with LSD should drop right into the front IFS 3rd of 1986-95 4WD Trucks & 4Runners. The carrier in your 1998 is the same as the '86-95 IFS differential.

The only true way to find out would be to remove the 3rd member from the front axle and physically inspect it for an LSD.

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GEO TRACKER / SUZUKI SAMURAI PERFORMANCE CAM
4x4 AnswerMan,

What kind of cam would you recommend for a 1993 GEO Tracker 4x4 automatic with a/c?

Robert S.


Hi Robert,

According to Calmini, their Mid-Range Camshaft should help increase your horsepower and torque from 2200 – 5500 rpm. They have one that fits the 1989-1994 Suzuki Sidekick, which is very similar to your Geo Tracker. Best thing to do is either call or email Calmini directly for more information. More info at http://www.calmini.com/.

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PLACES TO OFF-ROAD IN ILLINOIS
4x4 AnswerMan,

Looking for places to off road near Joliet.
 Tony D.


Hi Tony,

A local 4x4 club in your area recommends “The Cliffs Insane Terrain.” This 300-acre off-road park is located in Marseilles, IL.  More info at http://www.thecliffsinsaneterrain.com.

 

Also, if you have time, check out the Joliet Mud Turtles, a local Joliet off-road club http://www.jolietmudturtles.org/.

Enjoy!

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GORILLA HYDRAULIC RAM ASSIST
4x4 AnswerMan,

 I'm one of those "Monkeys" that builds full hydro and assist from farm equipment rams and knowing where to tap box. My setups turn 54" tires and do not fail. This isn't rocket science, boys; it's bi-directional hydraulic pressure versus flow, power versus speed. Stack a couple of #5 machine washers behind the bleed off valve in the pump and the pressure is more than sufficient. Someone could set up a system themselves for under $200 and it will work flawlessly. With the right bore (1.5") Stroke (8") and piston (1") You can make an off-the-shelf and easy-to-replace, non-exotic hydro assist for 1/3 the price.

Yours Truly,
600 lb. Gorilla

Letter sparked by:
Project Retro F-350: AGR Performance Rock Ram


 


Dear Mr. Gorilla,

Thanks for rattling the cage. This is the first time we’ve been contact by a primate who is bananas over hydraulic ram assist. We’re glad you have found a way to make your own home-brewed hydraulic assist at the zoo. Maybe you can give us more details and photos on how this all works.

In our opinion, the AGR Performance hydraulic ram assist system is still a great option for those looking to add more steering power to their 4x4 driving.  With a proven track record, all the necessary hardware and hoses--the AGR Rock Ram is a straightforward modification. Having the peace of mind that it’s going to work out of the box is worth its weight. The last thing somebody needs is a hydraulic pump failing or ram locking up on the trail if they didn’t do the job right.

Now we’re not flinging poo at your setup, and we encourage you to send more info to editor@off-road.com.  It will help those knowledgeable in tractors and farm equipment, like yourself, brew up their own hydraulic ram assist for their 4-Wheel Drives.


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