4x4 AnswerMan – Your Trucks and SUV Questions Answered

Apr. 30, 2013 By Jaime Hernandez
A classic Toyota FJ55 Land Cruiser (a.k.a. Iron Pig) rolling down a trail near Ouray, Colorado.

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.

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4x4 AnswerMan,

I have 2001 Ram 1500 4x4 5 spd 5.2L and am considering a Yukon gear hub conversion. Good idea? Do you know what rotors are used?
Sam Chicas


Hi Sam,

I did a little digging and found an article in Off-Road Magazine that states they use a Ford Dana 44 5x5.5-lug brake rotor. You can read more here.

Whether this locking hub conversion is worth it or not, its really up to you.  If you find yourself going through front hub bearings frequently, or really want to beef up your front axle and have the ability to free spin when not using 4x4, this might be just ticket. There might also be a slight increase in MPG if you’re looking for that extra nudge to justify the purchase.

What ever you decide, good luck.


Hello 4x4 AnswerMan,
I have a 1998 Chevy 1500 4x4 extended cab short box with a 5.7 Vortec and a 4-inch lift. I live on a dirt road and I was wondering what would be the best air intake I could get for it that the dirt wouldn't make it bog down?


Hi Jesse,

If you live in a real dusty area, I would recommend using your factory air box with a dry media or high-flow air filter. There are a number of companies that make quality filters for you truck.  We’ve been running a K&N Filter on our K1500 Chevy Z71 for over 10 years and it has worked well. It does tend to attract dirt because of the oil, but we just check at every oil change and after a big off-road trip. Clean as needed. Same goes for paper and dry media air filters.  

If you want a little more performance, a cold air intake system will work well, but it might require a pre-filter cover to help keep fine particles out of the engine.

Good luck.


4x4 AnswerMan,

Can the 1992 Tracker automatic version be towed "all four down" behind a motorhome?
Joe Unser

Hi Joe,

According to several RV sites we referenced, your 1992 Tracker should be towable behind a vehicle with all 4 wheels on the ground ONLY if it’s a 4x4 model. The transfer case will need to be shifted into NEUTRAL for it to work. Also, don’t forget to unlock the steering wheel with the key so it can move freely when in tow.

For more flat towing tips, please check out our Off-Road.com Forum:

Happy Trails!


4x4 AnswerMan,

I have a 99 Ford Expedition. The 4x4 worked last year, this year when I engage it I get a dash light but don't hear anything. Usually when I engage it I can hear it now nothing. I have checked the fuse and changed the transfer case fluid still no four-wheel drive.


Hi Rob,

It’s amazing what happens to a vehicle when the 4WD isn’t used, especially these newer models with electronic transfer cases. I’m not a big fan of them. For some reason, the shift motor freezes on them if they are not used frequently. It doesn’t matter what make or model. Give me a hard shifting manual lever any day.

Enough rant; try following any electronic wires going to the transfer case or front axle. Double-check the plugs to make sure they are dry and making good contact. Sometimes they get moisture or back off the plug, rendering your 4x4 inoperable. If this all checks out, look for any rodent bites in the wiring that may be causing a short. Don’t laugh, it happens.

You can also try smacking the actuator at the transfer case and front axle with a hammer to see if that frees it up. If none of these tips work, you may have a bad front axle actuator or transfer case shift motor. This may especially be the case if you have a “Service 4x4” light on.  You can either try replacing yourself or take it into a shop for service.

If the future, try to engage your 4WD at least once a month to ensure it works when you need it most.


4x4 AnswerMan,

I have a 95 Tacoma Ext Cab. V6 3.4l engine. My code is a/tm b03a/a340f. I know it says I have a 4:10 but when I do the tire spin check and count the revs of the drive shaft, it is approx. 3.8+- times per 1 rev of the rear wheels (both spin same direction). I need to change the diff and want to get exactly the same. My diff looks exactly like the V6 turbo/tundra one. What ratio do I have? 4:10 or 3.90+-?

Thank you.

Wow Jeff,
Sounds like quite the conundrum.  VIN Numbers and diff tags only tell part of the story. The only sure way to know what gear ratio is packed into your differential is to actually crack that 3rd member open. You can do a teeth count on the ring and pinion to determine your actual gear ratio.  Here is the formula. 

Ring Teeth / Pinion Teeth = Gear Ratio

e.g. 39/8 = 4.88

Good luck.


4x4 AnswerMan,

I have a 2008 Dodge 2500 Cummings pickup with a 4-inch lift. Rims are 20-inch with 325 aspect ratio tires. Over 65 mph, on a smooth road, all is fine, riding on glass. As soon as I hit a patch of roughness, the truck begins to shake almost uncontrollably, as if out of balance. Warm weather not so much but cold weather is terrible. Front end is tight with dual steering stabilizers installed. I suspect bad shocks feeling as if I am pogoing on springs.

Michael Ward

Hello Michael,

What you are describing is also known as “Death Wobble.” It’s a horrible experience, especially since it usually happens at high speed. There’s a great deal of debate of what the cause may be, ranging anywhere from worn front suspension components to under-rated tires. 

What some off-road suspension manufacturers that specialize in Heavy Duty Dodge Ram Trucks have found is that “Death Wobble” on the Dodge Ram 2500/3500 diesel trucks is attributed to running a non-compatible tire.  Your truck came equipped with Load Range E tires from the factory, and that’s what you should be running.  Sure you can run Load Range D, but the sidewalls will be softer, making them prone to harmonics that result in “Death Wobble.” The sidewalls on some of these tires are not strong enough for the weight and forces associated with heavy diesel solid axle trucks.

If you still have your factory wheels and tires (Load Range E), throw those on the truck for a couple of days and test the truck.  I can almost guarantee the death wobble will be gone.

Shocks and steering dampers may help but will only band-aid the real problem. That said, if your shocks have over 50k miles on them, it’s time for new ones. You can also double-check all the steering components, ball joints, knuckles, etc. Do it with the vehicle on the ground and also with it lifted off the ground. With wear and tear, there may be some excessive play in one of these parts—which will only add to the “Death Wobble.” Get it fixed and get it tight.

Best of luck and please be safe.




4x4 AnswerMan,

Will a 95 8-inch diff fit a 99 4x4 4runner? It’s been hard to find.

Hi Marshall,

It should fit if it’s off a 4Runner. It will not fit if it comes from a Toyota Tacoma, as the internals are different even though it is also an 8-inch. To keep things simple, try to stay with a 1996 – 2002 Toyota 4Runner with the same gear ratio.


4x4 AnswerMan,

I have a 1977 GMC that will not stay in four wheel drive high or low, it will pop out of gear.  Just wondering what it could be thanks

Hi Jeff,

Based on the year of the truck, I’m thinking it has some miles and wear. Chances are the transfer case may need some servicing. You can try simply changing the fluid and adjusting the shift lever to see if that helps. If you recently lifted the truck, you may also need to make the shift lever opening larger, as body movement may be causing it to pop out of gear. If any of these cheap tricks don’t work, then you might need to take the transfer case out of the truck for a closer inspection. It’s very possible the shift fork, among other parts, may need replacing. If the vehicle has a lot of miles or has had a hard life on the dirt, a rebuild may also be in the cards.

Try the simple things first.





Amazing truck, when are you going to add the supercharge kit?

Letter sparked by Shop Build: Slee Off-Road Toyota 80 Series Land Cruiser

Hi RJ,

Thanks for resurrecting this great 80 Series Land Cruiser build. Last we spoke with the owner, this Cruiser was built for overlanding and exploring. The idea is to keep the motor as stock as possible both for reliability and ease of servicing, so probably no supercharger anytime soon for this FZJ80.

Don’t get me wrong, superchargers are great, but for the money, they don’t seem to pack impressive numbers at low RPM where most of 4-Wheeling is done. They also require premium-unleaded fuel, which can be a problem in remote places.

It would still be pretty cool to have if you have an extra $4k laying around.


4x4 AnswerMan,

I have an '86 MK SD33T which has spun its crankshaft pulley and elongated the keyway in the crankshaft, apart from replacing the crank with a new key. Any ideas how to repair it?
Allan Rudd

Hi Allan,

I feel your pain. I had a similar experience and it put my 4x4 out of commission. To be honest, find yourself a good machine shop that specializes diesel engine rebuilds. They should be able to tell you if the crankshaft can be saved.  They may be able to weld material onto the crankshaft and mill it back.

Good luck.


Hi 4x4 AnswerMan,

I have a Toyota Hilux model 1980 4 cyl with an 18r engine. I want to replace this engine with a bigger one. What should I put?

Deeb Teeny

Hi Deeb,

I really like these early Toyota pickup trucks. If you are simply looking for a little more horsepower, but would like to keep the reliability Toyota is known for, I would look at 22r or 22re.  One is carbureted and the other is fuel injection. 

If you want to go crazy, then maybe a Toyota V6 or Diesel engine. It really depends on your budget and what you are looking for (power, reliability, cool factory, etc).

Whatever you end up doing, we highly recommend you try and get a complete engine/ transmission / transfer case setup with all the associated electronics. It will make life and the swap much easier. You can also do a custom marriage of parts to yield your ultimate Toyota.


4x4 AnswerMan,

My truck is stock height front and back. I just want a softer ride unloaded. I used to pull 5th wheel, done with that so most of the time unloaded. Did you end up leaving all 3 of the original height packs in or did you remove any? I would like the truck to be level if possible.


Letter sparked by Project Dodge Ram Mega Cab: KORE Recon Rear Suspension

Hello Dave,

By simply replacing the overload springs with the KORE Recon rear mini-pack, you should get a much softer ride and still keep the full tow capacity. It’s not a super plush ride, but it is an improvement, especially when empty. As for the little metal spacers under the leaf pack, we left ours in. The truck does sit taller in the rear when empty.  If you are looking for a leveled suspension look that matches the front, then we do recommend taking these metal spacers below the leafs out. How many exactly will depend on what you carry in your truck (e.g. tool box, aux diesel tank, topper, etc). It may take a few tries to get it just right. While you’re at it, we highly recommend you consider getting some new shocks. We’re really happy with our Bilsteins.


4x4 AnswerMan,

I have a 95 Chevy extended cab Z71 with a 5.7L. I have the service engine soon light that keeps coming on. I don’t have an OBD1 reader. How else can I find out what is wrong with it? Also, on a very low budget, how can I increase horsepower and fuel mileage? I just bought this truck a few months ago, so I don’t know what all has been done to it. I did a tune up and a fuel filter.

Thanks for your help,

Hi Neil,

You’re off to a good start by doing a tune-up and replacing your fuel filter.  This should help your truck run smooth and ensure it gets the best MPG. You can also keep your tires at optimal air pressure for added fuel economy on the road. As for the “Check Engine” light, there is the old paper clip trick that might work on the OBD1 system. 

You need to use a short jumper wire or paper clip to ground the diagnostic terminal. Put one end of the jumper wire into the ground terminal and the other into the test terminal (see illustration). 

A is Ground; B is Diagnostic test terminal (Photo Compliments of Hayes).

Turn the ignition to the ON position, but make sure not to actually start the engine. The “Service Engine” light should flash, giving you the trouble code. 

Count the flashes carefully. There should be a long flash, followed by a pause, then two more flashes. This is equivalent to Code 12, which means the diagnostic system is working properly, and it is therefore able to deliver good intel. After Code 12, there should be other codes that will be displayed if there is a stored record. The system will repeat the codes two times, so get ready to decipher the code.

Flash, Pause, Flash, Flash, Flash = Code 13 (Oxygen sensor circuit open)
Flash, Flash, Pause, Flash = Code 21 (TPS sensor out of range)

Below is a list of the most common OBD1 codes for 1995 and earlier GM vehicles.

OBD1 Trouble Codes Chart (for vehicles made before 1995)
12 System normal
13 oxygen sensor circuit open
14 coolant sensor high resistance or shorted
15 coolant sensor circuit low or open
16 direct ignition system (DIS) fault in circuit
17 cam position sensor fault
18 crank or cam sensor error
19 crank sensor circuit fault
21 tps sensor out of range
22 tps sensor signal voltage low
23 intake air temp sensor out of range, low
24 vehicle speed (vss) sensor circuit fault
25 air temp sensor sensor out of range, high
26 quad-driver module (computer) circuit #1 fault
27 quad-driver module (computer) 2nd gear circuit
28 quad-driver module (computer) circuit #2 fault
29 quad driver module (computer) 4th gear circuit
31 cam position sensor fault
32 egr circuit fault
33 map sensor signal out of range, high
34 map sensor signal out of range, low
35 idle air control sensor circuit fault
36 ignition system circuit error
38 brake input circuit fault
39 clutch input circuit fault
41 cam sensor circuit fault, igntion control circuit fault
42 electronic spark timing (EST) circuit grounded
43 knock sensor
or electronic spark control circuit fault
44 oxygen sensor lean exhaust
45 oxygen sensor rich exhaust
46 pass-key II circuit or ps.pressure switch circuit fault
47 pcm-bcm data circuit
48 misfire diagnosis
51 calibration error, mem-cal, ecm or eeprom failure
52 engine oil temperature circuit, low temperature indicated
53 battery voltage error or egr or pass-key II circuit
54 egr system failure or fuel pump circuit low voltage
55 a/d converter error or pcm not grounded or lean fuel or frounded reference voltage
56 quad-driver module #2 circuit
57 boost control problem
58 vehicle anti-theft system fuel enable circuit
61 a/c system performance or degraded oxygen sensor signal
62 engine oil temperature high temperature indicated
63 oxygen sensor right side circuit open or map sensor out of range
64 oxygen sensor right side lean exhaust indicated
65 oxygen sensor right side rich exhaust indicated
66 a/c pressure sensor circuit low pressure
67 a/c pressure sensor circuit or a/c clutch circuit failure
68 a/c compressor relay circuit failure
69 a/c clutch circuit head pressure high
70 a/c refrigerant pressure circuit high
71 a/c evaporator temperature sensor circuit low
72 gear selector switch circuit
73 a/c evaporator temperature circuit high
75 digital egr #1 solenoid error
76 digital egr #2 solenoid error
77 digital egr #3 solenoid error
79 vehicle speed sensor (vss) circuit signal high
80 vehicle speed sensor (vss) circuit signal low
81 brake input circuit fault
82 ignition control (IC) 3X signal error
85 prom error
86 analog/digital ecm error
87 eeprom error
99 power management

To clear the code from your vehicle, simply disconnect the positive (+) battery terminal for a few seconds. This should shut off the “Service Engine” light, but it will re-appear if the problem has not been fixed.

Once you get the Check Engine problem sorted out, you can move into building more horsepower with a clean bill of health. The most cost-effective mods are high-flow intake filter and exhaust.  You can work up from that.

Good luck.


Isuzu 4x4 Special Purpose FTS Trucks are used in Australia to help fight bush fires (Photo Compliments of Isuzu Motors Ltd).

4x4 AnswerMan,

I have a FTS33 Isuzu 4x4 truck. I wonder if you can advise any PTO winch that I can use? How about any supplier for super single wheel for my current dual wheel with 8 studs?

Thank you,
Sam Amar

Hello Sam,

The FTS Isuzu lines of trucks are impressive 4x4 machines. As far as a PTO winch, I don’t have a specific manufacturer in mind, but I would think that an industrial or military grade winch for a 2.5 Ton truck would work great. If you can’t find a PTO, I would consider an industrial grade hydraulic winch for your truck. I’m sure your big turbo diesel engine has more than enough power to handle it.

As for the super single wheels, I’m not really familiar with any foreign manufactures that make them specifically for the Isuzu FTS. I only know about Hutchinson who makes them for US Military vehicles. I’m sure you can find one in your country if you do some research. Try finding a military surplus business that deals with Isuzu 4x4 trucks. They should be able to help you find what you need.

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
March 2013

February 2013
January 2013

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