thanks serious for the info.....! sounds like the switch of a automatic to a standard trans in a 87-88 4x4 with 4.11`s and just 235 r15's would be maybe close to the 4d56t diesel rpm range!!!in mine i did it this way (replace a f*&ked 1987 3 speed automatic transmission with a 5peed standard trans ) my speedo guage is out on 235 r15's tires and is out about 8km.... 90km is 98km etc in 5th gear..! can anyone else weigh in on this???? Is this pretty close for for highway cruising!!!! Or should one go to 265r 15`s????? what is ideal rpm for this engine for fuel economy??? (p265r15/75 is 31/10.50/15 in inches)
http://api.viglink.com/api/click?fo...N2bRu3bNmziA&jsonp=vglnk_jsonp_13700214021206
5 speed manual 4x4 pickups have 4.37 gears
89-93 automatic 4x4 pickups have 4.44 fdr gears.
87-88 5 speed manuals also have the 4.44 fdr
87-88 3 speed automatics have 4.11's in the 4x4
I don't know if mazda ever built a auto in 87-88 with the overdrive transmission. This would be the same 3 speed jatco (nissan) transmission with the overdrive unit in the front of the tranmission.
I'm also in the ever so s l o w process of building one. I installed a 4d55t in an 87 last year, but didn't build it as there was lots of bearing mess in the pan. Parts are near impossible to find here in the states unless you're willing to go with the china made stuff or pay major money and talk to the guys in perth, au. I did aquier an 83 d50 turbo diesel last year and drove it threw the summer. Engine it it needs work, but I'm planning something of a hybrid mod motor for it based on fuel ecomony. I was only getting 25 at best cruising at 60 in the d50. I do also have a b2600 with the 4.11's that I think I'll try out. Even with the gas engine and the 4.44 or the 4.37 the engine is spining way too much.
I would like to know Jeff how you got away with using the b2600 gas pan with the mitsu diesel flywheel? The 4d55 fly wheel has clerance problems with the oil pan. I would like to know as I would like to use the gear reduction stater and not the gas b2600 one.[/QUOTE]