1988 Ford Bronco II valve noises?

Hello,

I am on the second of these broncos with the 2.9 and both have lots of noise from fuel injection or something, but I sure don't think its valve noise. Sounds sort of similar though.

but not as bad as the 'sewing machine

I remember a lot of those engines back then had mechanical lifters. They put some in the pickups and even the Aerostar occasionally. I don't know if the Bronco II could have had one also. If so, that would be a huge source of noise unless adjusted regularly. A trained ear would be able to tell.

You'll get other answers/opinions; but broken/loose valve keepers are one (very expensive if not fixed) cause of valvetrain noise. I can personally verify that one. Dropped valves are not conducive to the block; head(s); piston(s) or your wallet.

Another is lifters and/or oil problems. The 2.9 has hydraulic lifters; and they do "drain down" (get empty) when the vehicle sits for a few days. That will cause a hell of a rattle for a short time until they refill with oil. That's fairly normal. But if the oil pressure is low or there's severe sludge blockage on the oil galleries feeding the lifters; it ain't gonna stop.

If you have a Ford "oil pressure?" gauge in the dash; don't trust it. It's just an idiot light in disguise. It only shows no-half-full; with no real scaling. It will show "half scale" with anywhere between 5 and

What I'd do on the valve clatter is add one of the commercial oil flushes and run it for a few miles to clean out the passages (and the lifters as well-they get gummy as well); then change oil *AND* filter. Run the next oil change "short" (less than 500 miles) and do the flush again; with another oil and filter change. (reason is that the sludge may not gome out all at one time; and it can clog up the filter.)

As for other problems: Automatic trans: The AO4LD is pretty weak as stock. Ford designed it with 6 "planet gears" in the carriers; but the beancounters cut it down to 3 each. A good rebuild fixes that and a myriad of other problems. Raising the line pressure means harder shifts; but better life.

Manual trans : Also weaker than it should be. I'm no expert on these; but I've heard that a later ('92 on) tranny is far better.

Rear driveshaft: Weak CV joints and "high angles" cause problems. Most any driveline shop stocks a replacement with double Ujoints that cures that.

Other than that; it's a decent rig if you know how to maintain it. The other major problem is a lack of aftermarket goodies. What's out there is either damned good but pricey or stuff you wouldn't want on a phoney riceracer. ( I saw a Festiva with a wing and the rest of the horseshit; about gagged.)

Hope this helps

good grief

first off: it's 'A4LD'

second: the 6-gear planets did not appear until the advent of the 4.0 engine

ALL earlier versions had 3-gear planetaries

third: the weak spot is the OD drum, specifically, the return springs which bow outward under centrigugal force and get mangled by the inner clutch hub when the band slips and the engine drives the OD assemble at 3X engine speed

amd a 'good rebuild' does not necessarily mean 'raising the line pressure; what a good 'shift kit' does is to raise line pressure FASTER in response to throttle opening

now, before you start in on me for 'nit-picking', or tell me all about the A4 and how you know all out it (because you once owned a vehicle equipped with one), let me say that I've 'had the drill' with incorrect information on transmissions.......here, in alt.trucks.chevy, and in alt.autos.dodge.trucks

anyone posting incorrect information is going to get corrected, and let the chips fall where they may; I'm sick unto death of 'internet wisdom', not a week passes without some potential customer coming into my shop clutching a sheaf of printer paper and declaring that they have 'researched it on the internet' and 'knows exactly what is wrong' and 'knows exactly how much it should cost to fix'

TS

This is helpful. I am getting lots of things fixed and they told me the exact same thing about the valves and cv joints. I bought this for $1300 and am putting about $3,000 into it. Almost no rust so hopefully it will be worth it.

thanks TL

I have never seen a old 2.9 in a bronco that did not tick (though some more so than others). They must have used lifters in them that were prone to failure or with piddle valves that were easily fouled. It is annouying but nothing to get upset about because it is not easy to fix and it will not really effect engine life either.

All I can say is that's what I found in the Ford literature. If you go looking on trans fluid cans; they also call it an AO4LD.

So why was the carrier on mine formed and drilled for 6?? I don't mean just "holes"; but full machined at same dimension.

That's the usual fail mode; I didn't say the planet gears were *the* weak point. That's the one that "getsya" a few (40-60) thousand miles after the OD drum fix *if* the trans was "just patched" as was done by a lot of Ford dealers under warranty.

You *are* correct; but the phrase 'raising the line pressure' has been used for so long that using the 'correct' terminology confuses most people.

To each his own I guess. I'm not up on auto trans after about 83. I never did it as a business; either. I don't do much wrenching on my own anymore; my day job hurts the ol' bod too much.

I am going to ask you nicely (this time) . Did I lie to the original poster?