new member intro with some tech questions

Ok I recently bought a 91 explorer 2wd 5 speed I have a few questions on. I figured I would introduce myself (names Aaron) I bought the truck off a friend for 500 bucks to be a winter ride to keep my nice stuff off the road. I have always wanted a first gen explorer though it needed a windshield an exhaust a radio and speakers along with shocks. All is done aside from shocks and everything in the truck works as it should. There are some noises I'm a little concerned about though.

some back story on it may be helpful. It lived in Texas until 03 when the original owner gave it to the guy I bought it from who brought it to michigan where it has been ever since. Before it it was sold it had a complete new rear end from drum to drum installed. Paint is a bit faded and the rockers are a bit rusty but no other rust. It has 240k on it but 100k of that was being hauled behind an rv (it still has the rv tow hitch on the front, it makes a good battering ram so I'm leaving it on lol)

4 years ago it popped a head gasket and he bought brand new heads for it and replaced all the accessories (water pump alternator, ps pump, and a tune up and radiator) then he parked it and just drove it around during the block now and then. It runs like new. And the clutch though still original is strong no slipping at all. It also has the 3.73limited slip diff.

There are a few things I was hoping some of you with experience with these might be able to answer for me. For starters though all tie rods and ball joints seem tight it is clunking over bumps in the front end occasionally ( I'm sure this could be due to the original blown shocks BUT the steering also seems loose, as in I have to turn the wheel quite a bit before the wheels actually start to move. About 1/4 turn before it starts to turn. Maybe that normal for these, hence me asking you guys.

The most concerning thing for me is the transmission seems to be Making a whining sound. No vibration just a whining sound. Sounds a lot like a supercharger whine. Maybe it's normal but it's fairly loud. I'm not sure if it's an issue or these just have an abnormally loud tranny. I ONLY hear it when it's under load. If I let off the gas it goes away. Get back on it and it comes back. I don't hear it in neutral or coasting only with my foot on the gas and in all forward gears.

One other thing which may or may not be related is the speedometer wanders a bit sometimes. Sometimes it's steady, sometimes while running down the road at a steady pace it will wander and swing back and forth 3-5mph.

Any insight on any of these things would be greatly appreciated.

Welcome to the site.

Clunking from the front suspension is usually the radius arm bushings, they wear from age and suspension travel and replacing them with polyurethane bushings gives a firmer ride and longer life. Clunking can also be from the ball joints, especially the lower ball joints which wear on these and will be worn out so much the bottom of the steering knuckle moves nearly a half inch in either direction. You can check for ball joint play by jacking up the front suspension one side at a time, and either grab the bottom of the tire and pull it outwards, or stick a long handle tool like a shovel or long steel bar under the tire and pry up while looking at the lower ball joint and see how much it moves. Loose wheel bearings, loose axle pivot bushings, and even loose radius arm brackets or loose axle pivot brackets are also possibilities, but much less likely.

Transmission might just be worn if it's the A4LD automatic, but you could try changing the ATF with some Dex/Merc ATF in case the noise is because of old, dirty fluid or someone changed it with the wrong fluid. The whine might also be the rear axle rather than the transmission, the 8.8 differential is known for the whine it makes, and it needs to have the stock weight attached to the differential to dampen the whine. Could be that the new axle didn't get the weight attached to it so the whine is there.

The speedometer needle bouncing is usually just the cable binding in the sheath, fix is to pull the instrument cluster, pull the speedo cable out, and lube it with graphite, they make spray-on graphite just for the purpose, or you can mess with the powder graphite in a tube. Don't use grease to lube a speedo cable.

Alright. I was hoping the clunk in front was just the blown shocks. As I stated I checked the ball joints and tie rods and there was no play. How would i check the radius arm bushings for play. There was no play in anything i could find on the front end. As I also stated the truck is a 5speed. The sound doesn't sound like it's coming from behind. It sounds like it's coming strait up from the transmission. And as I said it's only with a load. If I take my foot off the gas, push in the clutch or take it out of gear it stops whining.

Blown shocks usually just give a mushy ride or cause bouncy, poor handling, but you can get a clunking if the shock allows the suspension to bottom out and hit the bump stops. The most common cause of the front suspension clunk on a 91-94 Explorer is the radius arm bushings, though. Some people "check" the ball joints and tie rods, either visually or just by grabbing the wheel and shaking it, but not giving enough force to actually check if there is play in the lower ball joint.

You can't really "check" the radius arm bushings, except visually, to see if they look worn, cracked, or are dry or getting hard if they are rubber. They "wear" on the inside, so you need to at least pull the big 28mm nut on the end and remove the washers and rear bushing and plastic insert to get an idea of what shape they are in. Sometimes even good bushings make noise because the nut bottoms out on the threads of the radius arm, making it so the front and rear bushings aren't compressed together as much as they should be, so sticking a big washer on the radius arm under the nut can keep that from happening.

The trans might be the syncros, but because of the driveshaft, what is really the rear end whine can be transmitted through the transmission and sound like it's a trans issue when it's the rear end whine or something related to the rear axle. With the Limited Slip, if the gear oil doesn't have the anti-friction additive, it might also make noise. Sometimes the additive that comes pre-mixed with gear oils doesn't do the job, and you need to get the right friction modifier from the dealer.

You can change the ATF, the manual M5OD uses the same Dex/Merc ATF as the Auto A4LD, and using the wrong fluid, either too thin or too thick, can cause issues and noise.

Alright I will have to have a look at it. It handles fine besides the shocks and being a 500 dollar winter ride I'm not to concerned about the clunk as long as it's nothing that's going to screw anything up. Sounds like something that can wait for it to not be 12 degrees outside. I don't just jiggle the tire to check ball joints. I'm not a moron... lol. I bought this thing and checked it out for all the typical stuff. Then I had surgery on my stomach and had only put a few miles on it so I didn't notice these few things, I can't exactly check it now. It's a minor clunk and is only occasional. Since I know all the main things are tight I thought I would see if there's a common issue. Which apparently there is.

As for the Trans noise it's definetely the transmission. It doesn't make the noise in 4th when it's in direct drive. Plus the rear only being 10 years old with only 6 years of actual use I doubt it's has an issue. It wasn't a rebuilt rear it was put in by the dealer all new from drum to drum. I would guess it's maybe just a bit work inside. I was just wondering of the whine was common to this tranny. It's definitely not the syncros they are in very good shape it shifts extremely well. Even this morning at 12 degrees. The fact that it shifts so well made me hopeful the whine was just something this tranny tends to do. I'm going to change the fluid when I can actually climb under it again when we get a warm day. I'm liking this truck more and more as I drive it though. The 3.73 gear and 5 speed gives it very decent power delivery and it's solid and smooth on the freeway with the cruise set at 75. Come summer it may get new rockers and some paint. I will probably take the 31x10.5 bfg all terrains off my truck (only 5k miles on them but I want to upgrade to a 33x12.5 on it) and throw them in this. It looks like they will just fit on this explorer.

If the clunk is the radius arm bushings, it's usually not an emergency replacement item, but if left alone too long, the radius arm bracket will get damaged since a worn bushing allows the radius arm to slosh around in the bracket and so the hole the bushing goes in gets expanded and distorted.

The main transmission issue with the manual M5OD is the plastic slave cylinders, which go out and then require dropping the transmission to replace. Transmission whine isn't usually an issue at all, which is why I suggest looking at the rear end or otherwise change the fluid in case someone put some newer thin fluid in instead.

3.73 and a 5 speed will make for a snappy ride, usually the 3.73 came with the 4 speed auto and the 5 speeds got a 3.27 ratio. You can run 31's with the 3.73 rear, but 33's are pretty big and it's better to have 4.56 gears for those. 33's will "fit" into the wheel wells, but you won't be able to steer the front wheels. You'll need to lift the suspension about 4-6" to get the 33's to fit properly. Easiest lift is a 5.5-6" that flips the rear axle to go under the springs. Some people do a body lift and a smaller suspension lift, then fit 33x10.50 tires instead of 33 x 12.50.

Just adding.... yeah, I had this too, I replaced the RA bushings, which helped. Replacing the ball joints was what really took care of it.

I'm not looking to put a 33 on this thing. I'm putting those on my 90 sierra. I want to put the 31x10.5 tires that are currently on that truck on this. From the looks of it they appear they will fit with no lift. I think come spring I will go ahead and replace all the ball joints and the ra bushings. I would do it now but it's cold outside and I'm not to worried about wearing the tires on it since the fronts are slightly dry rotten anyways. Another reason I want to put my 31's on it. I figured it would have a 3.27 ratio in it but the door tag doesn't lie. I don't have the original window sticker but I do know it was a special order. It has every option available for an xlt even the sunroof and I know they wanted a locking rear. Probably couldn't find one and had to order it.

31 x 10.50 will fit with almost no rub, but if the front coils are sagging some from age, the tires will rub on the front sway bar and maybe the radius arms if they are wider 31's rather than narrower ones like BFGs. You can lift the front some with washers that are 3 inches in diameter and have a 1-1/8 hole, stack them up under the coil spring seat to make up for the lost height and you restore the steering and alignment geometry, plus it puts the suspension beam rather away from the bump stops in case that's what's causing the clunk.

The door sticker is meaningless if the rear axle was replaced with something else - hopefully the axle they put in also has a 3.73. I don't think too many XLTs came with a 5 speed and 3.73 rear, especially 2WDs in 1991. Kinda nice, almost like what an SVT Explorer might have been back then.

The original owner is who had it replaced and it was done by the dealer so I would assume it was replaced with the same axle it came with. It definetely has some guts. It's got new stock sized all terrain tires on the back right now and it will turn them no problem if I punch it in first. I always wanted a really clean first gen limited to drop a 5.0 and a t5 in. I like this truck so much I may just go down south and find one when this one dies in me. (Not sure if replacing the rockers and doing paint is really worth the trouble when I can probably find one reasonably cheap down south with no rot) I'm not sure if the stock springs have any sag in them but at 240k miles I wouldn't doubt it. Do 4x4 springs sit any higher then the 2wd or are they the same? I wouldn't mind picking up the front end an inch if I can do it cheaply and safely. I don't mind a little rub at full lock on the frame or suspension with the 31's. I just won't turn it full lock, not a big deal and I could always add a spacer. I just don't want any rubbing on the bumper or fender.

You can do the rocker repair with scrap metal and just patch it up if it's not too bad, but if the metal behind the rocker is really gone, and the dog leg panel is badly rusted or falling apart, then you either have to fab stuff up from sheet metal or buy the pre-made replacement panels to weld on. You can also just cut the rockers off below the doors and weld on box steel, which is sometimes way less expensive than replacement sheet metal. You can also just cut the rockers and put on the plastic side skirts.

4WD coil springs will probably sit higher than 2WD springs since they have a higher spring rate, plus there were different spring codes for vehicle with manual and auto transmissions, and for vehicles with and without A/C, so springs from a 4WD auto will sit higher and might level out a 2WD manual.

You can also get aftermarket coil spring from Moog, the CC868 springs are the heavy duty ones and will probably lift the front end higher than stock for only $50-70.

The lighter rate 2WD stock springs will probably give more travel and a better ride though, plus it'd be cheaper to just throw some washers under the springs to lift however much you need to level the front with the back.

Well I'm not necessarily worried about leveling it unless it's needed to run the 31x10.5. I just want to run them because i have them and they have about 90% tread. As for the rockers it does need the dog leg on one side I did think about just welding on some metal where it needs and throwing the plastic side skirts over that. I may just do that. The truck needs paint too so I may just not worry about it. This is my 5th vehicle and I bought it just for winter use. It's sort of nice having a vehicle I can take anywhere and not care if it gets dinged or dented lol. I just want it mechanically sound and I would like to run those tires because I already have them. If I can fit them with no lift that's fine. All the leveling kits I found were 2". I think 2" would set the front higher then the back. I would post a pic but I either can't or can't figure out how.

One of the lower ball joints did have a very small amount t of play when I rechecked everything yesterday so I went ahead and ordered new moog upper and lower ball joints, moog ra bushing kit (the blue ones) and Kyb shocks for all 4 corners.

It is a good idea to do whatever repair you can, since something is better than nothing, and just leaving it to rust away will eventually allow the rust to spread and take out the whole rocker and eventually the rear fender and then you'll be dealing with a more extensive repair plus having to clean up water that made it's way to the interior, which usually gets soaked up by the carpet insulation, and requires removing the seats, carpet, and interior panels. Easier to just patch up the rocker or at least cut off the rust before it gets worse.

Cutting off the rocker at the bottom is a "fix" rather than just patching it since the rust is caused by water and snow/salt getting into the holes that the plastic side skirts plug into, which then has nowhere to drain out. Cutting the bottom of the rocker prevents anything from sitting in the bottom of the rocker, and you can still keep the rest of the rocker so the plastic side skirts have the necessary mounting points. You can just prime and paint the exposed metal with spray paint after cutting, or even use rubberized under coating, then put the side skirts back on over that and you've fixed the issue.


The 2" lift springs aren't a "leveling kit", since the rear isn't 2 inches higher than the front. You just need a few washers to level the front end with the back, which is more about restoring stock height and alignment, but can also give the slight lift needed so 31's won't rub. They should fit anyway, but the negative camber from spring sag also affects the ball joints and other parts since it puts them under more load when the vehicle is driven than if the front end was restored to stock height and perfectly aligned.
Leveling the front with washers back to stock height should reduce tire wear and allow more suspension travel for a smoother ride.

Where could I get washers that big and how thick should I get them. I looked at it closer today and the front is only about a half inch lower then the back. It is a very small difference. If this setup acts anything like the front suspension on my 90 sierra a 2" leveling kit (spacer) that goes under the coil spring is actually only about an inch thick but lifts the truck 2". I don't want to lift it more then a half inch in front. I need to do this when I do the ball joints and ra bushings soon before I get it aligned. So how thick should I get the washer and where do I find the right size.

From someone who started with a 2wd first gen almost 4 years ago, I can tell you that you have a leg up on what I had.

I had a 92 2wd 5 speed with open diff 3.27 rear, it did everything I needed it to except climb an icy hill.

D4 is the code under axle on the drivers door sticker for the LS 3.73 rear.

With my latest acquisition of my 93 sport, the LS 3.73 is freaking awesome, and I have yet to kick it into 4wd yet. My comparison is between my current 93 and an old Durango my wife had with the LS 3.55 rear, and I locked the Durango into 4wd more than I care to remember.

Oh to fix your transmission whine, 1 full quart of lucas trans fix the rest dextron/ ford specific ATF. I did this to my old 2wd and it almost silenced the whine.

Tip of the year: after draining the fluid and installing the drain plug, open the fill plug (leaving drain pan under trans) remove the shifter (3 torx bots hold shifter in) put in Lucas trans fix first, then the rest with the correct ATF stopping then fluid drains into drain pan, install fill plug.

I like this method because the bottle and small tubing into the fill hole sucks and takes forever. Choose your preferred method.

Ya the first thing I did was check the door tag expecting the 3.27 although I knew it was a limited slip. I was happy to see the D4. Judging by how it drives and rpm I would say it's accurate. In 5th at 70mph it's turning just a hair over 3k rpm. I think a 3.27 would be more in the 2500 range at that speed. I've driven it on icy roads the last few days with no trouble getting traction at all when I want it even with basic all seasons on the front with maybe 30% tread. I bet I wouldn't ever miss not having 4wd if I threw my 31" bfg all terrains on it. Also no trouble not having traction when I dont want it either though. It power slides pretty well lol. I've put about 250 miles on it so far I definitely like driving it. Just did a 60 mile trip in it with the wife when we could have taken her 14 fusion lol. I can't wait to get the front end squared away and the new shocks on so it's not clunking skipping around and pulling left.

I just prefer driving trucks and suv's for some reason. I have a 13 focus ST I bought 2 years ago and haven't broke 10k miles in. Despite it being a blast to drive and fairly modified I still drove my mint 90 sierra more then half the summer. With no a/c lol. (It's minty and also not stock but is a base model with zero options no a/c no carpet just a 350 and a 4.10 limited slip standard cab short bed) luckily this gets much better has mileage then the 8 -10 mpg that beast gets lol.

I think 70 is about 26-2700 rpm with the 3.73 I know 70 with my old truck that had 3.27 gears was around 21-2200 rpm.

You can get big washers at a fastener/hardware suppy, check your local yellow pages listings under "fasteners". Usually a specialty fastener shop will have them since someone needs to supply big nuts, bolts, and washers that the big box stores do not.

The washers are usually 1/8 in. thick, so you use anywhere from 1 to 4 stacked under the spring seat to make up the height difference.

The twin I-beam front suspension on Fords gives around 1.5 times the lift of whatever washer/spacer you use, so just two washers for 1/4 in. total height should get you about 3/8 in. of lift.

You may not even need the spacers since a 1/2 in. height difference isn't much, and trucks and SUVs have a factory rake so the back end sits higher so it won't sit as low when loaded. Best bet is look at the tires from the front of the vehicle about 10-20 ft in front of it, and see if they look like they have negative camber. That and look at how close the I-beams are to the bump stops.

You may also want to do the ball joints/radius arm bushings prior to doing any lifting with the washer, since new ball joints can fix alignment/camber issues. I still think washers are great to have since they allow for easy height adjustment, and usually they are needed on first gen Explorers due to spring sag from age, but if a vehicle is already aligned without spacers/washers, adding them just creates positive camber that needs to be adjusted for with alignment bushings.

Alright thanks for the info. And Mt cribb you were right the speedo bounces around so much at those speeds it's hard to tell but at about 2700 rpm it was bouncing exactly between 65 and 75 so I'm assuming that was 70mph lol.

I'm noticing an issue with my brakes now unfortunately. I didn't inspect the rears but I did the fronts and they still have at least half the pad left and appear to be wearing evenly. The brakes are just a bit weak feeling. Slightly spongy but mostly just weak feeling. It feels as though the rears are doing nothing or next to nothing. I figured it just had a weak system but every now and then, it did it twice before and it did it 3 or 4 tines today, I hit the brakes and instead of going halfway down before any braking occurs (another thing that strikes me as odd) the pedal felt firmer and braking started right right away not halfway down the pedal travel. It also stopped much easier and more evenly. I.e. it felt like the rear brakes were working. Now I'm thinking there's an issue instead of before just thinking like a lot of ford from this Era it just had an inadequate braking system. I was thinking master cylinder. But I read there is a rear abs thing that can give issues with getting pressure to the rear in these. Any ideas?

Change brake hoses (25 a side). They may look good on the outside but could have failed. Since rubber expands a failed hose can cause weak brake pressure.

I changed a hose and caliper a few weeks ago on mine and it helped immensely.