als804
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- kimcheon, ROK
my m1008 truck is on highway for most of drving. when i run at 60mph, i thought i need Over Drive gear. one day i luckly found Surplus Delivery van and then bought 2WD 4L80E behind of 6.5 DIESEL at affodable price. why i was lucky, actually here korea, really hard to find GM cars. most of cars hyundai and Kia you may not want. and i alwyas do things on low budget. so i decided to go FULL MANUAL VAVLE BODY MODE without expensive $ $ controllers. i will write the swap for another who is insterested in.
1. transmission + transfer case assembly removal.
you need to unbolt metric 6 bolts at the forque conver and inch-sized 6 bolts at the transmission housing, and unpug transmission cooling lines & vacuum line.
i found the heads of two bolts at bottom of the housing were broken. opps, loosen bolt normally results in broken
2. th400 with factory adapter and bling-bling gm 15724745 adapter at right. ( you can use factory crossmemeber, and becareful 4 mounting bolts for crossmemeber, 2 mounting botls for adpater)
you have to get this adapter othewise you need to grind the factory adapter. there is kind of mounting ring which has specific diameter at adapter . i don't know correct terminology. th400 ring at outputs side matchs factory adapter. but 4l80e ring could not to the factory. that's why you need new style adpater.
the 6 bolts-pattern of 4l80e or th400 is the same but 4l80e could not insert inside of the factory adapter.
be cautious with two meteric threaded ( M10-1.5p) bolts for mounting crossmember. and take a look at mount height is relatively very lower than the stock adapter height. this tells that you need spacers beteween new adapter and crossmember if you use stock crossmemeber. and width of two mouting bolt for new adapeter are a bit wider than width between stock bolt holes.
summary : with new adapter, you should drill wider holes for mounting of adapter and crossmember and need spacers between stock crossmemeber and new adpater to raise the front driveshaft flange for bolting front driveshaft. you may know 4l80e is 2~3inch longer than th400. So you have to move stock crossmeber to rear side about the distance between front and rear bolt holes of the crossemeber. this means the front mounitng hole at the factory crossmember can be bolted with the rear mounting hole at the frame. understand? you just drill only two holes. you can use existing two holes.
3. if you get 2wd 4L80E.
here south korea 4L80E is really hard to see. 4l80e i got is 2wd so i have to convert it to 4wd.
two things are neceesary.
A. cut the output shaft to shorten it as 4wd output shaft is OR buy 4wd output shaft.
B. remove holed plug for lube rear yoke and get solid plug inserted.
4. Bolting the transmission to the engine.
Lifter is necessary. Just know that there are two key holes between the bottom bolt hole and its upper bolt hole at transmission. Before bolting, you should insert the key holes
5. Rear and front driveshafts should be modified . I shortened rear driveshaft about 40mm ( 1.57inch). Be careful to keep rear and front yokes in-line
1. transmission + transfer case assembly removal.
you need to unbolt metric 6 bolts at the forque conver and inch-sized 6 bolts at the transmission housing, and unpug transmission cooling lines & vacuum line.
i found the heads of two bolts at bottom of the housing were broken. opps, loosen bolt normally results in broken
2. th400 with factory adapter and bling-bling gm 15724745 adapter at right. ( you can use factory crossmemeber, and becareful 4 mounting bolts for crossmemeber, 2 mounting botls for adpater)
you have to get this adapter othewise you need to grind the factory adapter. there is kind of mounting ring which has specific diameter at adapter . i don't know correct terminology. th400 ring at outputs side matchs factory adapter. but 4l80e ring could not to the factory. that's why you need new style adpater.
the 6 bolts-pattern of 4l80e or th400 is the same but 4l80e could not insert inside of the factory adapter.
be cautious with two meteric threaded ( M10-1.5p) bolts for mounting crossmember. and take a look at mount height is relatively very lower than the stock adapter height. this tells that you need spacers beteween new adapter and crossmember if you use stock crossmemeber. and width of two mouting bolt for new adapeter are a bit wider than width between stock bolt holes.
summary : with new adapter, you should drill wider holes for mounting of adapter and crossmember and need spacers between stock crossmemeber and new adpater to raise the front driveshaft flange for bolting front driveshaft. you may know 4l80e is 2~3inch longer than th400. So you have to move stock crossmeber to rear side about the distance between front and rear bolt holes of the crossemeber. this means the front mounitng hole at the factory crossmember can be bolted with the rear mounting hole at the frame. understand? you just drill only two holes. you can use existing two holes.
3. if you get 2wd 4L80E.
here south korea 4L80E is really hard to see. 4l80e i got is 2wd so i have to convert it to 4wd.
two things are neceesary.
A. cut the output shaft to shorten it as 4wd output shaft is OR buy 4wd output shaft.
B. remove holed plug for lube rear yoke and get solid plug inserted.
4. Bolting the transmission to the engine.
Lifter is necessary. Just know that there are two key holes between the bottom bolt hole and its upper bolt hole at transmission. Before bolting, you should insert the key holes
5. Rear and front driveshafts should be modified . I shortened rear driveshaft about 40mm ( 1.57inch). Be careful to keep rear and front yokes in-line
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