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4 Wheel Drive/SUVs/4x4 blinking lights


on my 99 explorer the 4x4 lights are blinking 6 times then stop ,it does engage when switched but at speed in 4x4 auto it makes a roaring noise it increases and decreases with speed what could it ,i've been told speed sensors or shift motor or vaccum lines how do i find out or what do you think


It's possible that the problems are speed sensors, or shift motor, vacuum, etc., but the roaring noise sounds more like a mechanical, or gear problem in the transfer case.

I would take it to a reputable transmission shop that is familiar with 4x4s, and have them check it out, before it freezes up, or breaks a case.

Without, actually listening to it, it's really hard to evaluate the actual problem.


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Carl Brandt


Will discuss suspensions, lifts, lockers along with tire suggestions. Trail ratings and possible requirements needed for specific type of trails. Safety equipment and what you should carry with you. Certified off-road instructor. I am not a mechanic, and 4-Wheeling is a hobby, so if I can't answer a technical question it is due to my mechanical knowledge being related to vehicles that I have owned, or have worked on. I do not have manuals on all vehicles, and I suggest that you obtain a repair manual for mechanical problems and do some research before asking your question. Most mechanical questions can't be answered completely without looking at, or listening to the vehicle in person.


40 plus years of 4 wheeling in a variety of vehicles. At the present time, my major off-road rig is a 94 Jeep Wrangler with a spring over and a 1 1/2" suspension lift. This gives me a total lift of 7" or so. I have lockers front and rear. I have removed the track bars, and sway bar for maximum articulation. I am running a stock 2.5 ltr 4 cylinder with a Jacobs ignition along with a cold air high flow filter. It has 4.56:1 gears with a Dodge NV4500 transmission along with a 3.8:1 Atlas II transfer case. This gives me a final ratio of 105:1 in low gear/low range. Other vehicles I own, are a 96 Ford F-250 with a 6" lift, posi rear end, 36" Hummer tires, 5 speed with a fuel injected 460 ci engine, an 87 Samurai with an 8" lift, Ford 9" rear end with a spool, Chevy Dana 44 front end with an electric locker, 5.88 gears, 16% reduction in high range and a 6.5:1 low range with 35" Baja Claws, and a stock 2003 Grand Cherokee Overland. Trails I have run are the Rubicon (10 times), Dusey Ershim, Fordyce Creek trail, McGrew trail, several trails in Moab, Utah along with local monthly runs.

Lost Coast 4x4's Cal 4-Wheel Corva UFWDA Blue Ribbon Coalition

Certified off-road instructor - Certificates in engineering/electronics

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