A couple of questions

[soloist3]

I own a 1998 Ford Explorer Eddie Bauer 4x4 w/ the 4.0 SOHC engine and had just a few questions. First off, I am trying to isolate a "clunk" noise that ONLY occurs while slowing down to a stop (or just near stop). Second I just had the tranny replaced and I am getting, on average 12mpg, when before, with the old tranny (which only had gears 1,2, and 4 working) I was getting 19-21mpg in the same driving situations. Also, there seems to be an excessive "rattle" (or perhaps engine resonance sound) that occurs right around 2400-2600RPM, that you can feel through the floor.

This truck has a classic design, that I still don't think has been outdone by any other SUV out there. I want to keep it but I wonder how much this might all cost me to fix? I have a few ideas I have yet to explore regarding the issues but ANY suggestions you all might have would be greatly appreciated.

 

[williams.cory]

Well since you have the SOHC then the rattle you are hearing is more than likely to be the timing chain tensioners. Do a search on them here on explorer forum. Those SOHC are very famous for that

 

[soloist3]

Timing Chain tensioners? Damn, hope that isn't too expensive. What about the "clunking" noise? It appears that it occurs both when I approach a stop or when during moderately hard acceleration while moving slowly? Could it be U-joints? Transmission mount? Or something worse?

Last thing, all of these problems, EXCEPT the gas mileage issue occurred before the transmission was replaced.

 

[williams.cory]

well replacing the tensioners is a HUGE pain in the ass and takes a while to do. So if you took it to someone then yes it will be pretty expensive. I have seen some people go a long time with their timing chain rattling, like 30,000 miles or more. Just take it easy on the old gal and it should last until you can get it fixed. How many miles are on it?

The clunking is probably just the drivetrain, mine does the same thing when slowing to around 10 MPH and it shifts to 1st gear, its just some play in the driveline.

As for the gas mileage im not sure. How are your driving habits? Are you any more aggresive after replacing the trans? When up to speed how many RPM's are you at? This might seem like a dumb question, but somehow did the buttion get hit to turn the overdrive off? Maybe you have been driving around is 3 gears....lol.

 

[soloist3]

Hmm.. Sounds like it's probably the tensioners then, btw, is a good idea to change the timing chains if you are going to do the tensioners or no? I have 126K on my engine and have NO history as to the last time the timing chains or tensioners have been changed.

Driving habits are pretty moderate; same as before the tranny was replaced (and I was getting 19-21mpg with only gears 1,3, 4; no 5th/overdrive either). I wonder how much it would cost to have this done? Also, which Explorer's are least likely to have these types of problems? Lastly, are there any similar, or better motors, that could be swapped in? Perhaps from a different year or model that don't have the same problems (well anything except the OHV 4.0 V6, that engine is just too weak for the hills I have to climb and whatnot).

 

[williams.cory]

You shouldnt have to replace the timing chain itself, just the tensioners...

A better motor, which is the best IMO, is the 5.0L V8!!!!! AWESOME motor! So much power and gets average 17-18 MPG. They are VERY reliable and have no issues with them at all. Mine has 215,000 miles and you wouldnt know it, still has all the power like new!! But I wouldnt drop a v8 into yours because since it has the SOHC that means it has the 5R55E which is a weak transmission( as you already know!) Best bet is to get rid of it and get a explorer with the v8 because that means it will have the 4R70W trans which is VERY good and tough transmission, most likey to never need a rebuild in its lifetime unless you get into serious miles or is put through heavy abuse.

 

[jlsparky7]

The clunk could be the slip yoke needing to be lubed or your u joints might be going bad.

Have you dont a differential flush? Here's a how to.
http://www.youtube.com/watch?v=CAiy8CN1JdE

+1 on the ford 5.0 being a bad ass engine. Haven't even driven might yet and I love it already.

 

[soloist3]

The 5.0 is looking better and better; it's funny, I told my brother that we should get the V8 and he said no because of the gas mileage, oh well I am going to start looking.

 

[williams.cory]

you shouldnt have let him talk you out of the 5.0!!!!!!!!!!!!!

gas mileage really isnt that bad. But they are great motors! Once you get one you will never go back to anything else. But if you do get one, try to make sure its a 98 or newer. If its 98 or newer than they have GT40 heads and a transmission fix ( cant remember what it was but it was really minor ). Not to mention they look just a little better IMO. But if you cant its really no big deal, shouldnt have any problems out of it if the previous owner kept up on maintenece...

 

[williams.cory]

Oh yeah, one issue that the 5.0 has.....if its a AWD then you might have problems with the transfer case in the future depending on how many miles it has. The chain in the case tends to stretch over time and eventually it will start to skip gears causing a real loud clunking noise under any acceleration. But if that happens you can always take the front driveshaft out and it'll be just fine for a long time until you can get it fixed ( if that does happen make sure its not the actual driveline because one end has a CV joint that has the same symtems when going bad ). But you shouldnt have any problems with that because they usualy start to fail around 170,000 miles or more, mine had 208,000 before going bad.