4.0 w/700R4 - Is it possible?

I am looking to change my 90XJ to an auto and was thinking about putting a 700R4 behind the 4.0. Does anyone know what kind of problems I would run in to. I am assuming that I would need some type of an adapter. The reason for the 700R4 is that I have access to some freshly rebuilt ones and they lack the need for a computer. I know I would need to adapt the TV cable to the throttle body and adapt the tranny mount, and driveshaft. Any and all help is greatly appreciated.

90red

It is possible and you're absolutely correct you will need an adapter, and you can get them from a few places. The two I know of are www.novak-adapt.com and www.advanceadapters.com but, I'm not sure if advance adapters will have one for what you want.

You'll also have to relocate your crank position sensor to the front of the engine. There is at least one kit out there to do this, but I don't remember who makes it. Seems like it was one of the stroker kit companies.

Steve

Willis said:

You'll also have to relocate your crank position sensor to the front of the engine. There is at least one kit out there to do this, but I don't remember who makes it. Seems like it was one of the stroker kit companies.

Steve

Click to expand...

Yeah, it's Hesco at http://www.hescosc.com

Just bringing up a possibility, that new isn´t necessarily better. I´ve got five broken 700R4's in the garage. A 1971 TH 350 still going strong, 2 727's still going strong (one a 74) and an 87/88/95 AW4 still going strong. For my money, most any tranny is preferable to the 700R4, two in the garage where strengthened/improved at additional cost. :doh:

90red said:

I am looking to change my 90XJ to an auto and was thinking about putting a 700R4 behind the 4.0. Does anyone know what kind of problems I would run in to. I am assuming that I would need some type of an adapter. The reason for the 700R4 is that I have access to some freshly rebuilt ones and they lack the need for a computer. I know I would need to adapt the TV cable to the throttle body and adapt the tranny mount, and driveshaft. Any and all help is greatly appreciated.

90red

Click to expand...

For the price of the adapter and the extra work needed for everything else, you would probably be better off just getting a used AW4. Already works, since its factory, easy to find and wont require alot of extra fab work to get it working right.

Thanks for all of the info guys. 8mud, I disagree with you, I have never had any problems with any 700R4's I have owned. I recently had one behind a 406 SB with 525 HP and 500 Torque in a 65 Chevelle and it never failed. But, everybody has there opinions and I am not out to tell you that you are wrong. The main reason I am going for the 700R4 is the overdrive auto and lack of need for a TCU and new wiring harness. Thanks again guys. I really appreciate the help.

90red

I've cratered two 700r4's on daily driver rigs. They are real picky about fluid level and have a tendency to fry the babbit bearings in the planetaries on 2-3 when low. I would be worried about running them at any steep angles for any length of time.

You can add me to the casualties list too.

I lost two 700R4's in my '88 GMC pickup, but my 2WD AW4 was going strong when I swapped it out for a 4WD box at 265,000mi. The 4WD is now just short of 200,000 and still doing great. I also recently lost a 46RH in my '95 Dodge Ram just short of 90,000mi, so the AW4 has been the most reliable automatic I've ever owned. Plus you can find used ones for a couple hundred dollars, so they are almost expendable too.

I´ve taken apart a couple of 700R4´s, out of curiosity. Was shocked at what I found. Chev. tried at least three major redesigns. Just couldn´t seem, to get it right.
Never seen one, even moderatly used, that lasted much over 50,000-60,000 miles.
I have a buddy, swears by the 700R4, he has 33,000 on his, guess we´ll see.
4L60 maybe, 700R4 never again.

I've been silent here, but now I have to say something. The 700R4 is a great transmission. I have seen numerous 700R4s go 300K with no problems. I have also seen them under numerous street rods with tons of horsepower and they hold up great. Why do you think so many street rodders use them? Well, one because you don't need a computer for the overdrive, but the other reason is because they are bulletproof and can hadle a LOT of horsepower. I've had a few that I was really hard on outlive the vehicles they were in. My dad and his friends build high horsepower street rods and run nothing but 700R4s and never have any problems. Also, a friend of mine had a 1/2 ton Chevy truck with the 700R4 go over 300K with rediculous abuse and it was still going when he sold it. He used to pull 8000 lb trailers with it all the time, way more than that truck was designed to pull. He blew two 350s by pulling too much with it, but that 700R4 just wouldn't die. If thats not a testinonial to a 700R4, I don't know what is. Everyone is entitled to their opinion, but I couldn't bite my tongue any longer. eace:

Do yourself a favor and go with the AW4. I have been in the transmission business for twenty years and the 700r4 is one of the worst for reliability. No matter how you beef it up or shift kit it it will never last as long as a AW4. My AW4 has over 200k on it and it runs sweet as the first day I bought it.

Maybe it´s the autobahn over here in Germany that does them in. Long runs at 80-100 MPH can´t be good for them. Extra tranny coolers, deep pans, bigger pumps, don't seem to help much.
Maybe somebody finally figured out how to make them last, 11 years after they stopped producing them. Guess anything can be made to work, with new internals. Out of the box or factory 700R4´s? Don´t think so. They had a class action lawsuit, because the things were failing right and left. Chev, finally gave them up, after a relatively short production run, compared to the 350 or the 400. Introduced the 4L60 for a few years until they changed to the L460E.
I have a 33 year old tow truck, with the original TH350 in it. Should have paid the extra hundred bucks for the TH400, but I`ve gotten pretty good service out of the old TH350.
Maybe the 700R4`s are great trannies, I´ve never had much luck with them. Know I´ve spent enough on rebuilds, to buy half a new truck.

there is only a few small differences between a 700 and a 4l60e. Its basically the same trans.
the sun shell, good servo, kevlar bands,1800 stall, 13 vane pump, a real trans cooler, and a HD/RV type shift kit will be the best bet for a 700.
Saying you have 200k on it isnt a justifiable comparison, since you havent run a 700 in an XJ. I cant count how many AW4s went bad in my stock XJ with 160 HP and whitewalls.
Ive smoked 4 700s in my XJ, and now I know what it takes to run one.
my Impala SS has a 4l60e which is basically a 700 with e-control and a weaker case, has 140k, with a 100shot of nitrous. I drive it like I stole it, and it doesnt miss a beat.
On that note, If I had it to do again (The XJ), It would be a powerglide or a TH400.
A stock 700r4 wont offer you any advantage.

Here's a write up on it: http://www.rockcrawler.com/techreports/aa_autoswap_yj/index.asp