gmc 6.2 v8 diesel gearbox
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sneakysnake
"There’s nothing new in originality"
Auto box? you mean automatic transmission? The turbo 400 was common on them. The bolt pattern is standard gm so a th350 would work but you may check the flex plate bolt holes to fit the torqe converter some plates have both sizes and some dont.
busch
Well-known member
400 should bolt right up get a shift kit for it there cheap good luck
RPM
The Rat Master!
A Chevy trans is not the same bolt pattern as a Olds or Buick. So which one fits the 6.2 diesel?
I am thinking it is the Olds bolt pattern, but not 100% sure. Can someone clarify that?
sneakysnake
"There’s nothing new in originality"
Sounds like there may be a few tweeks to the tranny on a diesel because of low rpm and shift points. Here is a guy trying to put a 6.2 tranny to gas
http://www.pavementsucks.com/board/thread-6-2-Diesel-trans
http://www.pavementsucks.com/board/thread-6-2-Diesel-trans
sneakysnake
"There’s nothing new in originality"
I think the 5.7 may have had a different pattern but I think the 6.2 used a chevy pattern,but im no expert.LOL
http://www.forgottendiesels.com/6.2_gm.html
Screamin' Metal
Well-known member
The 6.2 Deisels from the earily 80's to the late 80's were in the military trucks, M1008/M1009/M1028-1/2/3's, the civilian heavy-duty trucks C/K-2500, 3500's etc. They even cam in the early hummers, and was replaced by the 6.5 diesels. Was just a update thing.
The bolt pattern was the same as the BBC's, even things like the fuel pumps will bolt onto each others blocks.
The dist. drive hole is even the same, except on the diesel it doesn't drive a distributor, but a short 90 degree vacuum pump.
[P
We usually do the dual turbo thing with these motors and they run great...
The bolt pattern was the same as the BBC's, even things like the fuel pumps will bolt onto each others blocks.
The dist. drive hole is even the same, except on the diesel it doesn't drive a distributor, but a short 90 degree vacuum pump.
[PWe usually do the dual turbo thing with these motors and they run great...
Willowbilly3
A *real* tin magnet
Yup, same bell housing pattern as a standard Chevy V8. You will need a different converter and as mentioned you will probably need a different flex plate.
Torch
Extremely dangerous with a torch!!!
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like they said your chevy smallblock or bigblock tranny will bolt right up.
If the 6.2 already has a flexplate your part way there
If your replacing a 700r4 diesel tranny with a 700r4 gas tranny you prolly wont need a new flexplate. If your replacing a diesel th400 with a gas th400 or th350 you wont need a new flexplate.
But I don't think th400/300 and 700r4 flexplates interchange.
When the 700r4 went bad in my 82 6.2 diesel I replaced it with a th400 from an 85 3/4 ton that had a 350 gas engine.
I only needed to buy a th400 flexplate for a 6.2 diesel. the transmission already had the right torque converter.
the th400 has either a 3 bolt or 6 bolt converter. trucks got the 6 bolt converter in the diesels and gas trucks...same converter.
If you go looking for parts there are only 2 options for th400 the 3 bolt or the 6 bolt
If your running a th350 just put the 6 bolt th400 converter in it.
I never had a problem with the shift points. as a matter of fact I still manually downshifted and held 2nd gear longer when getting on the interstate.
One problem I had is my 6.2 had a 700r4 and had the electronic throttle position sensor on it. the th400 uses a vacuum switch on the injector pump to tell the vacuum modulator on the tranny what to do.
I just ran my vacuum pump right to the th400 without adding the vacuum switch to the injector
It operated in light throttle mode all the time but i wasn't towing.
*With full constant vacuum on the modulator it will upshift faster and run under it's minimum line pressure
*With no vacuum on the modulator it will upshift really late and might not go into drive at all. it will be really annoying the engine rpm ypu run at until it shifts to drive it's basically in kickdown mode all the time and shifts too hard
If the 6.2 already has a flexplate your part way there
If your replacing a 700r4 diesel tranny with a 700r4 gas tranny you prolly wont need a new flexplate. If your replacing a diesel th400 with a gas th400 or th350 you wont need a new flexplate.
But I don't think th400/300 and 700r4 flexplates interchange.
When the 700r4 went bad in my 82 6.2 diesel I replaced it with a th400 from an 85 3/4 ton that had a 350 gas engine.
I only needed to buy a th400 flexplate for a 6.2 diesel. the transmission already had the right torque converter.
the th400 has either a 3 bolt or 6 bolt converter. trucks got the 6 bolt converter in the diesels and gas trucks...same converter.
If you go looking for parts there are only 2 options for th400 the 3 bolt or the 6 bolt
If your running a th350 just put the 6 bolt th400 converter in it.
I never had a problem with the shift points. as a matter of fact I still manually downshifted and held 2nd gear longer when getting on the interstate.
One problem I had is my 6.2 had a 700r4 and had the electronic throttle position sensor on it. the th400 uses a vacuum switch on the injector pump to tell the vacuum modulator on the tranny what to do.
I just ran my vacuum pump right to the th400 without adding the vacuum switch to the injector
It operated in light throttle mode all the time but i wasn't towing.
*With full constant vacuum on the modulator it will upshift faster and run under it's minimum line pressure
*With no vacuum on the modulator it will upshift really late and might not go into drive at all. it will be really annoying the engine rpm ypu run at until it shifts to drive it's basically in kickdown mode all the time and shifts too hard
Torch
Extremely dangerous with a torch!!!
- Joined
- Jul 18, 2008
- Messages
- 1,627
new info
I bought an 86 c20 454 truck with no engine and tranny
The internet told me that 6.2's and 454's were interchangeable so when I put a 6.2 into the truck I had troubles....
the bolt holes wouldnt line up in the front mounts
I had to install the 6.2 frame brackest from the donor truck
that was 2 years ago. I threw a rod and am putting a 350 smalblock in it now.
I have put 454's in where there was a smallblock with no troubles so i figgure I can use the 454 mounts with the 350...
No dice same problem I had with the diesel
I get online...
And I discover...
that the 6.2 diesel and the smallblock chevy share the same engine mount and engine mount frame bracket and both are incompatible with the 454 brackets
so I put my 6.2 diesel mounts back in the frame...
and the 350 bolts right up perfectly...
there are only 2 torque converter options for a th400 and it isn't diesel and gas...
it's 3 lug or 6 lug
the 6 lug converter is a lower stall and is used in both diesel and gas trucks.
the 6 lug th400 converter can also be used in a th350
You need to mount your fuel filter so it's the highest point in the fuel system
Your cold idle circuit goes to the fast idle solenoid and fuel line heater (under the intake manifold) and gets wired through a temperature sender the same way you wire an electric choke.
Whatever you do...do not hook up an electric fuel pump...it wont run right.
the IDI diesels running a stanadyne injection pump (5.6, 6.2, 6.5, 6.9, 7.3) all use the pressure from the lift pump (your ordinary mechanical fuel pump) to control the govenor.
the lift pump for the diesels increase in fuel pressure as engine speed increases. the injection pump is calabrated according to standardized lift pump specifications.
Putting an electric fuel pump on, having a weak lift pump, or the wrong lift pump, having the fuel return lines misengineered, having a restricted fuel return... will send the wrong signal to the injection pump and it won't run right.
If you can figure out how mechanical injection works on a gas engine you can figure diesel injection... on a diesel the injection system works the same using different equipment. rather than having continual injection like with a hilborn unit...the diesel injection pump is also a distributor.
I bought an 86 c20 454 truck with no engine and tranny
The internet told me that 6.2's and 454's were interchangeable so when I put a 6.2 into the truck I had troubles....
the bolt holes wouldnt line up in the front mounts
I had to install the 6.2 frame brackest from the donor truck
that was 2 years ago. I threw a rod and am putting a 350 smalblock in it now.
I have put 454's in where there was a smallblock with no troubles so i figgure I can use the 454 mounts with the 350...
No dice same problem I had with the diesel
I get online...
And I discover...
that the 6.2 diesel and the smallblock chevy share the same engine mount and engine mount frame bracket and both are incompatible with the 454 brackets
so I put my 6.2 diesel mounts back in the frame...
and the 350 bolts right up perfectly...
there are only 2 torque converter options for a th400 and it isn't diesel and gas...
it's 3 lug or 6 lug
the 6 lug converter is a lower stall and is used in both diesel and gas trucks.
the 6 lug th400 converter can also be used in a th350
You need to mount your fuel filter so it's the highest point in the fuel system
Your cold idle circuit goes to the fast idle solenoid and fuel line heater (under the intake manifold) and gets wired through a temperature sender the same way you wire an electric choke.
Whatever you do...do not hook up an electric fuel pump...it wont run right.
the IDI diesels running a stanadyne injection pump (5.6, 6.2, 6.5, 6.9, 7.3) all use the pressure from the lift pump (your ordinary mechanical fuel pump) to control the govenor.
the lift pump for the diesels increase in fuel pressure as engine speed increases. the injection pump is calabrated according to standardized lift pump specifications.
Putting an electric fuel pump on, having a weak lift pump, or the wrong lift pump, having the fuel return lines misengineered, having a restricted fuel return... will send the wrong signal to the injection pump and it won't run right.
If you can figure out how mechanical injection works on a gas engine you can figure diesel injection... on a diesel the injection system works the same using different equipment. rather than having continual injection like with a hilborn unit...the diesel injection pump is also a distributor.
