I'm trying to catch up on maintenance on the 1996 4.0L AWD Aerostar (75,000 miles) that we picked up a couple of weeks ago. Tonight, I was underneath and noticed that the rubber seal on the front output shaft is missing.

Looking at Chiltons, it seems to be a straight forward fix. But being that I looked at Chiltons, I am not positive .

Can anyone tell me if there is anything special needed to replace the front seal, and also, what is the CRITICALITY of replacing it. Do I have to get on this right away, or can I schedule it for a couple of weeks out after vacations and baseball tournaments are over? I don't think the van will get any huge mileage between now and the end of July (maybe 1000 - 1200 total miles).

I've also got a few small leaks from the t-case itself. Can't tell if it's the rear mating surfaces of the case, or just loose drain and fill bolts (both were pretty easy to break loose, so I don't think they were quite tight enought to begin with). I'll monitor the case over the next few weeks and see where the leaks are coming from.

Also, the Check Engine Light is on. I was told that the code was something to do with the Evaporative Canister, but I am going to use a friends scanner this weekend and confirm. In the meantime, will it hurt to run the van a couple of hundred miles with the CEL on? (It did go out the last time I drove it for about 35 miles, so I think it is some sort of intermittent problem?? I've got no miss, ping or other engine symptoms right now).

I've already changed oil and coolant, checked PS fluid, changed the drive belt and the air filter. I've checked the tranny fluid, and while not new, does not seem terribly old or burnt. I plan on changing that within the next week. I also plan on cleaning the MAF and IAC in the next week or so. The brakes have a pretty good shimmy at higher speeds, so I am planning on new front pads and turning the rotors soon, too (or buying new rotors). After going for a quick test drive tonight, including a few stops from high speeds (80ish to 20), I noticed that the front wheels were pretty hot, but the backs were cool. Would this be *normal* braking distribution to the front brakes, or would warped rotors cause this heating too?

In the meantime, is there any other obvious work that I should consider doing on this right away?

thanks in advance,


Jeff

 

I am assuming you are refering to the front output shaft dust boot (bellows) as being missing rather than the actual seal which could not be seen. If so, you can drive it without incurring any real problems. Replacing it seems striaghtforward, except that getting the shaft out is nearly impossible without also lowering the front differential. Just unbolting the two ends does not create enough space to lower the shaft.

Leaks from the transfer case can be from the fill/drain ports as you mentioned, from around the gasket that mates the TC to the transmission, bad o-ring on the speed sensor, or more likely, from the air vent located on top of the TC. The later will happen if the TC was overfilled. Just throws it out. Reach up on top and see if there is fluid there also. If so, it is from either the vent or the speed sensor seal.

Check engine light could be something as simple as the gas cap not sealing properly. The evap cannister is just a box of carbon that engine vacuum pulls through. Rarely is there ever a problem with the cannister itself, but the error code covers all associated parts of the evap system. It is likely either the gas cap or the vacuum line is leaking. If your second effort to pull a code confirms the evap. system, then it should be fine to drive like that.

The front brakes account for nearly 65% of the braking capacity by design. After a few stops, the rear drums should be rather warm to the touch if not hot. If cool, the rear shoes are out of adjustment - a common occurence. The self adjusters do not seem to work all that well on these vans. Warped rotors have no affect on the rear shoes. Be sure it is not worn tie rod ends that are causing the shimmy rather than the rotors.

Sounds like you are getting everything into good shape for the trip. Last thing - check your tire ipressures and have a good trip!

 

Regarding the transfer case leaks, I would definitely check the speed sensor. I've had two of them leak, one within about a year of installation. I just replaced the "o-ring" (which isn't a true o-ring) on it with a real one and haven't had problems since. So, if it's leaking, don't throw the sensor away, just get a new o-ring from the hardware store (make sure it's compatible with oil).

 

Thanks for the replies guys!

1. Yes, I did mean the dust boot. I could not identify this particular part from the quick look I did in the Chiltons Manual. I'll keep an eye on it and figure out when would be a good time to replace it, if just for peace of mind...

2. T-case. I just sprayed a bunch of degreaser on it last night and presssure washed all the old gunk off. My wife drove it down to Woodland Park for the weekend (about 100 miles one way), so I should be able to get a good reading on any leaks when she returns. I'll be sure to watch the places that both of you mentioned, it seems that those fixes are easier than fixing a leak between the case units themselves.I've done front tie rods on my old Aerostar, so I'll check out the front suspension components when the van returns. It just *Seemed* that the pulsing was coming from the brakes themselves.

Thanks for the advice!