I need some advice, I have owned my 1983 diesel blazer for a year now. It has a 700r4 transmission. The transmission is done and needs either a rebuild or replacement. Should I rebuild it, replace it, or as some have done convert it to a manual nv4500? (It would be pretty BA to have a manual) Where should I buy the replacement/rebuild kit? Should I get a tranny from monster transmissions or just go to my local auto parts store? Also should I do it myself or pay someone? I have never done a transmission before but I do have the know how to figure it out. My thing is, is it worth my time and effort for the savings in doing it myself? My mechanic quoted me $2450. A new transmission and tourque converter runs about $1400 from what I have seen. Any advice would be great. My main goal is to make it reliable out on the trail and as a daily driver. Thanks.
Bob's right in that doing an NV4500 swap is more work than replacing your 700R4, but it's a doable amount of extra work if you want a stick. Swapping the pedal cluster was annoying (partial steering column removal is required). I opted to keep my automatic column rather than swapping that out, too. I snagged my clutch MC with the pedals. My firewall did NOT have markings where the MC was supposed to go (some do), so I had to figure that out. Brake pedals from trucks with hydroboost brakes are slightly different from the pedals in vaccum-boost trucks. Diesel flywheel is not the same as sbc flywheel. TH350s and your 700R4 have a 27-spline output shaft, the other GM trannies all have 32-spline output shafts, so you'll hafta find another transfer case or swap in a new T-case input shaft.
And for the NV4500s themselves, they come in 2 GM varieties (not counting the Dodge versions). From 93-94, the trannies used external slave bell housings similar to what the SM465 used (but the slave cylinder is on the wrong side. This bell housing will fit in your truck, but the slave sits below the starter...right where your front driveshaft wants to be.
I have one of these boxes, and I grabbed a hydraulic SM465 bell housing (with the slave on the driver's side) from one of the members on here and drilled & tapped the input face of my NV4500 to match (pattern is different). You can buy a custom AA bell housing to adapt patterns, but they were $400 last time I checked.
If you get a 95+ tranny, it will have a higher granny gear, a removable shifting lever tower, and the bell housing will be set up for an internal slave. I think internal slaves aren't as nice as external slaves, but adapting a hydraulic line sounds like more fun than adapting bell housings, thinking back through my parts-collecting phase. The two styles of NV4500 will not swap bell housings.
IIRC, High-impact sells the newer style.
And that's it. Should be a fairly straight-forward swap, but it will be more work than simply throwing in a 700R4. Read through my M1009 thread for pictures of the first half of the swap (haven't gotten further than that yet, my pieces are still scattered around the shop).
Oh, yeah...if you still have an OEM starter on that 6.2, it will be different from what the stick-shift trucks use. If you have a parts-store replacement, it probably is compatible. But if you don't, you'll hafta remove some metal from the nose. Pictures in my thread.
If you like rowing through the gears , do the NV4500. ............. I think it would be easier finding a doner truck with everything you need, rather than trying to track down the bellhousing for the diesel, t-case adapter for your existing transfer case, linkage, ect.
