4.6 4R70W vs. 5.4 4R70W
 

I recently purchased an 01 F-150 that looks like it needs a new transmission -- it's a 4.6L automatic 2WD. I have access to a 99 Expedition 2WD 5.4L that also appears to have a 4R70W transmission that I can get very inexpensively.

Are there any differences in the two transmissions? I do know that Hollander lists the transmissions for the 4.6 and 5.4 seperately.

Thanks!!

I know that they use a different torque converter. Not sure about the other things such as bolt pattern and such.

Why not pull the 5.4 and the tranny from the Expedition and use the whole set up unless it is no good?

Just a thought.

WigWag

There are differences....gear ratios, parts used in the transmission, the cooler, as well as the casing are just a few of the differences. If you can get your hands on a remanufactured transmission or a 2003 transmission, do it. The reman trannys are fully updated to the latest model year to ensure longevity and better overall performance. There are sometimes major changes made during the specific model years to address certain issues. In addition to that, the older one also may not last as long as a newer one. I was just in this boat about 2 weeks ago when the trans on my X died. My X now has a 2003 transmission, it shifts differently, and has learned a few new tricks, but what I was told made sense. Everything was properly explained and makes sense; I even got a second opinion to confirm everything. You may also want to shop around and get a few quotes on the repairs.

If anyone found this informative or helpful, please add to my reputation in the upper right hand corner. :)

Thanks for the replies -- 5.4 engine in the Expedition has been sitting in the open with the intake removed so it's not something I would try and use. The transmission would be very cheap but obviously doesn't do me any good unless it's a pretty close interchange.

What I'm concerned about is a dimensional and functional interchange between the two versions of the 4R70W. Hollander sometimes differentiates between similar parts due to the internal parts or internal design. In this case I would assume that going to a 5.4 transmission wouldn't create a problem strength-wise and would work if the electronic and mechanical connections were the same.

I've got access to a few junk yards and will try and will try and source a later model 4.6L transmission and torque convertor to replace the current transmission.

Thanks again for the replies.

The 4.6 and 5.4 4R's are dimensionally the same. The 5.4 however, has one or two more forward clutches (stronger) and I believe a harder planetary set. I have a 5.4 based 4R70W in my car (94 merc cougar) and it is dimensionally the same as the 94 4r that came out of it...of course the internals in mine have been worked over, but you get the idea. The gear sets are all the same ratio in all 4R's as well. Hope this helps

Joe

the 4.6 and 5.4 both have the same pattern. the 5.4 70w is just built stronger. it is a direct bolt up.

Learn from your mistakes! I have a 01 F150 5.4. I lost OD and reverse at only 39k. The dude told me it would cost $2200 to rebuild it. In my stubborness, I bought an 04 F150 tranny from a 4.6. Everything bolts up and matches to the T. However the speedometer output is about 10 times faster than the 01 tranny. So when I first drove it, the speedo said i was doing 70 when I was only doing 7mph. Shifted into OD and stalls it everytime. I bought a speedo changer but it is lousy. My ultimate goal is to fix the original tranny and put it back in. They are both 4r70w's and are only off by 1 number on the tag. Watch what year you swap to!

Yes, you definately need to keep an eye on what you are swapping in. In some cases, the output shafts have different number of teeth, some don't have any. From an 01 to an 04 is quite a leap. I would personally not get a rebuilt trans, there are too many things that can be put together wrong, not cleaned, etc., and you will have another blown trans in 20K or less. It's almost always cheaper to find a good used one.

Joe

all you need is the 04 speedo gear drive. not a expensive part. runs about 15.00 that will get the speedo working like it should. OR does yours use a VSS on the rear diff?

I don't know which year/model tranny will interchange with what. But if it were me I'd ask at my local junkyard. If you know somebody in the biz start there. If you can't get the answer there try Allison. here are some contact #'s:

http://www.hollander-auto-parts.com/...tact/index.asp

Havn't tried this myself. I'm sure if your nice and ask for help, you'll get the info you need.

Good Luck

Thanks again for the replies -- I lucked out and found a 70K miles trans out of a 2003 F-150 4.6L for $400 and had it put in for another $300 including a complete flush of the coolers and trans filter change and changing both seals. Works like a champ.

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About your transmission
 

Because that was 15 years ago. You responded to a very old thread.