edsjr1

Last Friday out of nowhere my truck lost reverse. I pulled into a parking spot, then tried to backup and nothing. It hasn't acted strange, not loud noises, all forward gears including overdrive work normal. No codes, no flashing O/D light, no clues at all

Sunday I noticed it will sometime crawl in reverse but doesn't have any power.

Last night, I tried to make it crawl in reverse......it finally flashed "Transmission Malfunction" on the screen followed by "Engine Failsafe Mode". I shut the truck down, restarted and the codes were gone. Put it in reverse again and while it didn't have full power it backed up without much issue.....I also didn't force it with a bunch of throttle though.

I read about sun shields and bands. I've read the reverse band can be adjusted, and I've read that it can't or it won't do any good.

I see something about a reverse servo

Also wondering if this could be a valve body issue and a passage is plugged or partially plugged.

I've watched a video and it doesn't look like rebuilding this thing would be horrible.

Any advice or ideas?

arichens

The only time I've had this happen the reverse band had just flat out snapped. Took it as a chance to rebuild the tranny.

techrep

iTrader: (1)

Any maintenance history on the tranny ? current mileage ? Has it ever been serviced ? Pan drop or Flush ? How is the fluid level ? did you check the shift linkage on the tranny itself ?

edsjr1

276K on it, I put a new motor in this truck this past spring. It's due for a fluid change but not overdue and it's been done regularly the entire life of the truck (I bought it new in '04)

One other piece of info.....the gear shifter doesnt lock in place in reverse but does in all other gears. I wish I had paid attention to that last night when it did actually go in reverse.

I haven't really done any diagnosis on it yet, pretty much just been searching the internet for info on it.

One thing I haven't been able to find out through vin decoder or anything is exactly which transmission it is, 4R75W or 4R75E....any thoughts on that? This is all I can find on it with the decoder. It's a loaded Lariat, only options it doesn't have is moon roof and premium sound. I do have an opportunity to buy a recently rebuilt transmission out of a '98 F150 FWD but I'm guessing that won't work in my truck.....which sucks because he only wants $450 out of it.

Trans Order Code44B, 44A
Trans Type4 4.0 min 4.0 max
Trans Description Cont.Automatic w/OD
First Gear Ratio (:1)2.84 2.84 min 2.84 max
Second Gear Ratio (:1)1.55 1.55 min 1.55 max
Third Gear Ratio (:1)1.00 1.0 min 1.0 max
Fourth Gear Ratio (:1)0.70 0.7 min 0.7 max
Reverse Ratio (:1)2.32 2.32 min 2.32 max
Transfer Case ModelWarner 44-06
Transfer Case Gear Ratio (:1), High1.00 1.0 min 1.0 max
Transfer Case Gear Ratio (:1), Low2.64 2.64 min 2.64 max

techrep

iTrader: (1)

Crawl under and look at the shift linkage on the side of the tranny..

edsjr1

That's the plan, unfortunately my garage configuration would make it hell getting the truck back out if reverse isn't fixed. I'm hoping to get it to go into reverse and back it in then investigate but probably won't do it until saturday....until then I'm just careful where I park

At this point I'm pretty sure it's a 45R75E

edsjr1

So the truck is in the garage with the pan off

No metal in pan
Magnet looks normal
Linkage is unhooked

Still won't lock in reverse at the shifter

Its got a center shift, any ideas?

HeathMc

Like Tech said you will need to crawl under and check out your shift linkage. If it finally went into reverse I wouldn't suspect the band breaking which I first thought it might be. Maybe release the shift linkage and try going thru the gears with your hand. Will need someone to set in it with a foot on the break.

edsjr1

Sunday I changed the fluid and put a TSS in it

Now, I get a block and a half from home and I get "transmission malfunction" followed by "engine failsafe mode" then it lists a code for the TSS and the failsafe mode and the O/D light is blinking. Shut it down, go another block and a half and it does it again

yesterday I started it, put it in reverse, felt it go into gear as normal and it idled backwards.....no way that band is slipping

Today, dropped the valve body out of it. No signs of anything out of the ordinary

Fluid smells normal

Anyone ever rebuild a valve body?

Any ideas? I'm still in denial that it's an internal problem

DigitalDad

What did you end up doing to fix the truck?