ok Iv got the 350, I ordered the nessesary crap from JTR.com. Problem is the I have an 87 4x4 and I was told I cannot use the 2.8L tranny for the 350, I need the 4.3L tranny witch is a 4x4 700r4, can I buy one off ebay and slap my transfer case on it? or do I need to go to a junk yard and find this magical tranny/transfer case combo? also going from the 2.8 to the 4.3/700r4 can I use my front and rear driveshafts? I really want to keep my 4x4 and any help would be greatly appreciated!

I still need a working 4x4 tranny to bolt up to this 350 if anybody has it

 

Relax....

The 700R4 behind your 2.8 is dimensionally the same as the 700R4 behind a 4.3L V6 or sbc engine. With one exception, the bolt pattern to teh engine. The 2putt8 700R4 is commonly called a 60 degree bolt pattern. While the 4.3L V6 and small block chevy V8 engines use a 90 degree bolt pattern. No, your 2putt8 tranny wont bolt up to the 350, however.......

GM used the 700R4/4L60 tranny in all light duty trucks, vans, and suv's. You wont have any problem finding a 700R4/4L60. In other words, all 1/2 ton pick ups, Suburbans, Tahoes, S10-Blazers, Astro vans etc, etc, etc, all have a donor 700R4/4L60. Your best option is to find one from a 4x4 truck/SUV.

The 2wdr version of the 700R4/4L60 tranny has a different output shaft, and different tailhousing then a 4wdr version. Get the 4wdr version. Get the t-case if you want, or run what you have. Or better yet, use your NP207 as a doubler, and get a NP231.

More good news, you wont have to change your driveshafts, tranny mount of any of thatstuff. The 700R4/4L60 trannies are all the same length, wideth etc, regardless of which donor they came from. The only exceptions is the 2wdr verse 4wdr as described above.

A 700R4/4L60 behind a fullsize truck is built a little stronger then one behind the S10 truck, however they can all be built to handle some serious power. 450 foot pounds of torque.

Personally, I think your best option is to find a 700R4/4L60 from '87-'92. "93 they went to 4L60E, electronicly controlled. Early 80's had relieability issues, although a rebuild will fix those issues and no doubt all of the early 80's trannies have been rebuilt at least once by now.

 

sweet! I dont car what you say, you are the blazer God

 

Thanks.
just info I learned while doing research and a little practical application.

 

I have a 700R4 with only 12k on rebuild. PM me if you want it.