Armed Polite Society
Main Forums => The Roundtable => Topic started by: Northwoods on May 30, 2023, 05:31:48 PM
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Bought a 2003 F-150 (4.6 V-8, RWD, automatic) with 260k miles. Knew transmission was sketchy but for $2k figured it was worth it. When it’s shifted in Drive (or 1st, 2nd) it won’t engage. Engages reverse just fine. It would take a while to shift into D when I bought it, and it was definitely best to let it warm up. But now it won’t engage at all. Transmission has plenty of good looking fluid.
Bad shift solenoid? Something worse? If not the solenoid what is likely?
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Automatic transmissions are the work of the devil.
:rofl: :rofl: :rofl:
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Automatic transmissions are the work of the devil.
:rofl: :rofl: :rofl:
I agree but that doesn’t change anything.
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Has the trans filter been changed and the screen cleaned?
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Has the trans filter been changed and the screen cleaned?
Not by me.
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A different tranny thread ...
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That's a common issue with the 4R70W. Unfortunately, it's usually also a death knell. Not totally, but enough.
Sounds like an issue with the forward drum as it's common to 1st and 2nd gear. 3rd, OD, and reverse engage on different drums/bands. My guess is either the clutches are toast or you've stripped the engagement splines. Both are caused by constant heavy towing. A lot of stop and go heavy towing, especially in hot weather, will kill the forward drum clutches in short order. Heavy towing with OD on will strip out the forward drum because of a piss-poor OD engagement design (for heavy use, not for regular daily driving).
Either way it sounds like a rebuild/replace is in your future. On the bright side, Ford only made a bazillion 4R70W transmissions. They were in pretty much every light duty V8 application Ford made in the late 90s and early 2000s. Shouldn't be hard to find one in a wrecking yard. Just be sure and verify it's for your specific application as there are several variants. Some transmission shops might even have a core-swap unit already sitting on the shelf.
HOWEVER...
Try a fluid/filter service first. It's cheap and there's a possibility, albeit slight, it'll help.
Brad
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Leaking o rings can also cause slow shift I to gear, as it takes longer to build the pressure needed to engage the clutch. I limped a C6 along for about two years with leaking orings by pouring some mineral spirits (like 1/2 a cup ish) in every couple months. The solvent will swell up the rubber seals and help them hold pressure. I don't remember for sure if the 4R70W has the same o-ring design, but I think it does.
Brad is also correct that abuse of the transmission often leads to the the 1-2 clutches failing, but if they've failed bad enough they won't engage I'd expect the fluid to smell burned, and for there to be some chunks of friction material in the pan. Unless the previous owner threw a fluid change at it to hide there abuse.
2003 with a quarter million miles? How much money are you prepared to put into a $3500 truck?
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Like dogmush, I would have expected burnt fluid, but yea, unknown history with regards to the previous owner.
I don't know a lot about the 4R70W, but I rebuilt an E4OD/4R100 by myself, ripped down to nearly individual bits. From that experience, my approach would be to drop the pan and take the valve bodies off. Carefully inspect the spool valves for debris or damage. If that looks good, put it back together, hook into the pressure port with a gauge and check pressures in each position. That would break this problem down into "Am I dropping this trans or not?"
DIY rebuild isn't hard, but it isn't fun. Tedious. You have to be very meticulous if it's going to go okay. I had to make a couple tools as well. Pending the above tests, in your case, I'd consider swapping in a scrapyard transmission. Look for something with lowish miles that was in an accident. If it was in an accident, at least it was running before it came to the scrapyard!
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Older E4OD rebuild here too. I swear, I nearly came near suicide on that one. First go everything was great, backed it out of the garage and then the flood came. Turned out I had the front bearing too tight and the fluid couldn't get back home fast enough so it pushed the front seal. No harm, no foul, learned an ancient chinese secret to beating clearance into said bearing. Put it all back together and fire it up, instant red flood. This time I was fortunate, the trans cooler lines were chafed and worn paper thin, one gave up. Easy fix, drove the truck another couple years. ( I forgot, it was even better. I looked down at the nifty little dental spatula I have that I had been working the big square seal in with. I was holding it backwards and using the dental chisel end. Lotsa tiny holes. next day air seal...)
My big takeaway from that is any chance you get to add a trans cooler, do so. I have a fragile year 700R4 sitting in my yard waiting for it to magically rebuild itself but I guess I will have to help it.
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Older E4OD rebuild here too. I swear, I nearly came near suicide on that one. First go everything was great, backed it out of the garage and then the flood came. Turned out I had the front bearing too tight and the fluid couldn't get back home fast enough so it pushed the front seal. No harm, no foul, learned an ancient chinese secret to beating clearance into said bearing. Put it all back together and fire it up, instant red flood. This time I was fortunate, the trans cooler lines were chafed and worn paper thin, one gave up. Easy fix, drove the truck another couple years. ( I forgot, it was even better. I looked down at the nifty little dental spatula I have that I had been working the big square seal in with. I was holding it backwards and using the dental chisel end. Lotsa tiny holes. next day air seal...)
My big takeaway from that is any chance you get to add a trans cooler, do so. I have a fragile year 700R4 sitting in my yard waiting for it to magically rebuild itself but I guess I will have to help it.
I'll admit I had mine in and out three times before it was right. Turned out to be a stupid problem. The pump housing is made of two castings bolted together. On the outside, the two parts are about a 14inch round circle. The bolted together halves fit in a bore in the bell housing. They rest on a flange with a gasket, which has fluid passageways. I had the two halves of the pump housing misaligned by about ten thousandths of an inch. Because of that, the assembly sat canted in the bell housing, resulting in a leak in the gasket between the housing and the pump assembly. It was a stupid problem that taught me just how pedantic one needs to be when dealing with automatic transmissions.
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...I'd expect the fluid to smell burned, and for there to be some chunks of friction material in the pan. Unless the previous owner threw a fluid change at it to hide there abuse.
...2003 F-150 (4.6 V-8, RWD, automatic) with 260k miles. ... Transmission has plenty of good looking fluid.
Fluid change/flush is presumed, probably right before sale. No way a 260K mile transmission is going to have decent looking fluid. Five bucks says sale was influenced by previous owner seeing first signs of trans failure and threw a fluid/filter change at it as an attempted quick fix.
Which begs the question... when they did the fluid/filter change, did they get the old filter seal out of the valve body before installing the new filter? Doubling up on filter seals is a common mistake and almost guaranteed to cause problems.
Brad
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Reading Nick and French’s experiences I will probably have it towed to a shop for any work. I don’t have the time, patience or ability to deal with crap like that anymore.
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On the relatively easy side I just swapped a valve body on the missus’ Subaru crosstrek. Nice of them to put it on top. 12 quart dry capacity and only able to squeeze six something in after a full drain and filter replacement. Subaru magic fluid at $15/quart. Going to fluid change it again soon. Subaru of course wants you to believe that the transmission is good for life like a maintenance free battery. ;/ The Internet nerds say change the fluid early and often. I tend to believe them.
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For planning purposes it looks like a remanufactured 4R70W for that truck should run you about $2k for the part. A used medium milage one is ~$1600 ish.
Add labor and shop supplies on top of that for the remove and replace.
If you are going to pay someone to rebuild your existing unit, it's going to depend a lot on what they charge for labor.
I'd expect this to be in the $2500-$3500 range depending on the shop.