K10 original tranny? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

70K10Hunter · 10-19-2012, 04:11 PM

OK, just took posession of a new to me engine crossmember and I am having fitment issues. What different transmissions came in these trucks?
I have a SB with a turbo 400 that came in the truck and it looks as tho the PO modified the crossmember to make everything fit.
The crossmember was moved forward (I believe)cut and rewelded and redrilled in the frame.
Is a turbo 400 longer than a turbo 350?

**special-K** · 10-20-2012, 09:34 AM

What truck are you working on?

70K10Hunter · 10-20-2012, 01:27 PM

1970 K10, thought the title would give it away. I know the engine was replaced it has a goodwrench 350 in it.

**special-K** · 10-20-2012, 07:19 PM

Oh,now I see your user name says 70 K/10. Some members have more than one truck or the name is from a truck they used to have. Anyway,in a '70 K-model you could have the Saginaw 3spd,New Process 465 4spd,or TH350 with New Process 205 transfer case. From what I've experienced,all used the same crossmember.

70K10Hunter · 10-20-2012, 10:51 PM

So the turbo 400 was not offered? Is the turbo 400 longer than the turbo 350?
I ask this because the engine crossmember has been moved forward three inches from the original mounting location.

kenbob87 · 10-20-2012, 11:46 PM

dont quote me on it but i do not believe the th400 was offered in the half tons until 76?
i wanna say they started putting them into chevy trucks the same time they started offering the 400 sbc

**special-K** · 10-21-2012, 07:54 PM

Correct,no TH400s in any K-models till later. I didn't know why the crossmember would need to move forward for the TH400...or any transmission. The adapter between the transmission & transfer case makes up for differences. I had a '71 Blazer that came with a 3spd o the column and a dinky little Dana 20 transfer case. I swapped-in a TH350/NP205 out of a '72 Blazer and never touched the crossmember. I had done 4spd to TH350 swaps,too,and same thing. Just bolt in.

70K10Hunter · 10-21-2012, 09:05 PM

so you guys are saying that a TH350 is the same length as a TH400?

SunSoaked · 10-21-2012, 11:17 PM

Quote:

Originally Posted by 70K10Hunter

so you guys are saying that a TH350 is the same length as a TH400?

Here:

70K10Hunter · 10-22-2012, 02:01 AM

Now thats what I'm talking about!!!
Thank you very much!!!
where did you get those drawings? cool
Its right there in black and white the cases are different lengths, slightly over 3"s which is what my engine crossmember was moved.
there will be no tailshaft as it is a 4x4 with a TC.

**special-K** · 10-22-2012, 06:25 AM

Yes,the TH400 is longer. So,why would the crossmember be moved "forward"? That's what has had me confused. Maybe show some pictures so we can see what's up. To put the TH400 in your '70 the TH400 transfer case adapter would have had to be used. In fact,possibly your transfer case is a newer one,too. There's an ID plate on the back of the t-case and it should have the year stamped into it. Also,does your truck have a SPID on the glovebox door? Does it say your truck was originally an automatic? FYI,'70 was the first year for automatics in pickups. Does you VIN begin with a K?

**Ridgeback** · 10-22-2012, 05:05 PM

You have two options when you use a 400 trans with the NP205 in a 69-72 4x4 setup. Either move the engine forward and leave the trans mount where it is or move the trans mount back and leave the engine mount where it is. In your case it looks like the PO moved the engine forward. I have done it both ways and I cannot say one was any better than the other for truck performance. However, moving the engine forward gives more space at the firewall and gives easier access to the distributor.

70K10Hunter · 10-22-2012, 05:58 PM

Quote:

Originally Posted by Ridgeback

You have two options when you use a 400 trans with the NP205 in a 69-72 4x4 setup. Either move the engine forward and leave the trans mount where it is or move the trans mount back and leave the engine mount where it is. In your case it looks like the PO moved the engine forward. I have done it both ways and I cannot say one was any better than the other for truck performance. However, moving the engine forward gives more space at the firewall and gives easier access to the distributor.

You are correct. It looks like the PO moved everything forward to avoid shortening the drive shaft,(much cheaper to drill holes than have shop work done)
Since I have seen the chart (Sunsoaked) showed it all makes sense now, so question answered.
I will be starting my build thread soon and I will explain all the things I have found on this truck.
I really appreciate all the help you guys give. I just have a need to find out as much about a rig that I can so that I can correct any jacked up mods that were done on things.

**special-K** · 10-23-2012, 06:28 AM

Ok,now I see. I thought you were saying the transfer case cross member was moved forward. I guess I was focused on transmission/transfer case since those were swapped. I have moved the engine forward on TH400 and 700r4 swaps. I think it's the best way on 67-72s,since the engine is crammed back into the firewall anyway..."and" you can leave the drive shafts lone.

10-19-2012, 04:11 PM	#1
70K10Hunter Registered User Join Date: Jun 2012 Location: Hill Country Posts: 435	K10 original tranny? OK, just took posession of a new to me engine crossmember and I am having fitment issues. What different transmissions came in these trucks? I have a SB with a turbo 400 that came in the truck and it looks as tho the PO modified the crossmember to make everything fit. The crossmember was moved forward (I believe)cut and rewelded and redrilled in the frame. Is a turbo 400 longer than a turbo 350?

10-20-2012, 09:34 AM	#2
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,862	Re: K10 original tranny? What truck are you working on? __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

10-20-2012, 01:27 PM	#3
70K10Hunter Registered User Join Date: Jun 2012 Location: Hill Country Posts: 435	Re: K10 original tranny? 1970 K10, thought the title would give it away. I know the engine was replaced it has a goodwrench 350 in it.

10-20-2012, 07:19 PM	#4
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,862	Re: K10 original tranny? Oh,now I see your user name says 70 K/10. Some members have more than one truck or the name is from a truck they used to have. Anyway,in a '70 K-model you could have the Saginaw 3spd,New Process 465 4spd,or TH350 with New Process 205 transfer case. From what I've experienced,all used the same crossmember. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

10-20-2012, 10:51 PM	#5
70K10Hunter Registered User Join Date: Jun 2012 Location: Hill Country Posts: 435	Re: K10 original tranny? So the turbo 400 was not offered? Is the turbo 400 longer than the turbo 350? I ask this because the engine crossmember has been moved forward three inches from the original mounting location.

10-20-2012, 11:46 PM	#6
kenbob87 Registered User Join Date: Oct 2012 Location: South Haven, MN Posts: 109	Re: K10 original tranny? dont quote me on it but i do not believe the th400 was offered in the half tons until 76? i wanna say they started putting them into chevy trucks the same time they started offering the 400 sbc

10-21-2012, 07:54 PM	#7
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,862	Re: K10 original tranny? Correct,no TH400s in any K-models till later. I didn't know why the crossmember would need to move forward for the TH400...or any transmission. The adapter between the transmission & transfer case makes up for differences. I had a '71 Blazer that came with a 3spd o the column and a dinky little Dana 20 transfer case. I swapped-in a TH350/NP205 out of a '72 Blazer and never touched the crossmember. I had done 4spd to TH350 swaps,too,and same thing. Just bolt in. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

10-21-2012, 09:05 PM	#8
70K10Hunter Registered User Join Date: Jun 2012 Location: Hill Country Posts: 435	Re: K10 original tranny? so you guys are saying that a TH350 is the same length as a TH400?

10-22-2012, 02:01 AM	#10
70K10Hunter Registered User Join Date: Jun 2012 Location: Hill Country Posts: 435	Re: K10 original tranny? Now thats what I'm talking about!!! Thank you very much!!! where did you get those drawings? cool Its right there in black and white the cases are different lengths, slightly over 3"s which is what my engine crossmember was moved. there will be no tailshaft as it is a 4x4 with a TC.

10-22-2012, 06:25 AM	#11
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,862	Re: K10 original tranny? Yes,the TH400 is longer. So,why would the crossmember be moved "forward"? That's what has had me confused. Maybe show some pictures so we can see what's up. To put the TH400 in your '70 the TH400 transfer case adapter would have had to be used. In fact,possibly your transfer case is a newer one,too. There's an ID plate on the back of the t-case and it should have the year stamped into it. Also,does your truck have a SPID on the glovebox door? Does it say your truck was originally an automatic? FYI,'70 was the first year for automatics in pickups. Does you VIN begin with a K? __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~ Last edited by special-K; 10-22-2012 at 06:30 AM.

10-22-2012, 05:05 PM	#12
Ridgeback Senior Member Join Date: Mar 2003 Location: Virginia Posts: 809	Re: K10 original tranny? You have two options when you use a 400 trans with the NP205 in a 69-72 4x4 setup. Either move the engine forward and leave the trans mount where it is or move the trans mount back and leave the engine mount where it is. In your case it looks like the PO moved the engine forward. I have done it both ways and I cannot say one was any better than the other for truck performance. However, moving the engine forward gives more space at the firewall and gives easier access to the distributor.

10-23-2012, 06:28 AM	#14
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,862	Re: K10 original tranny? Ok,now I see. I thought you were saying the transfer case cross member was moved forward. I guess I was focused on transmission/transfer case since those were swapped. I have moved the engine forward on TH400 and 700r4 swaps. I think it's the best way on 67-72s,since the engine is crammed back into the firewall anyway..."and" you can leave the drive shafts lone. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~



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