trans ?

[pmartinez]

I have a 1989 chevy one ton dooley that I have done a ctd coversion with a turbo 400 and gearvendor o/d 3. 54 dana 70. Now I want to turn it into a 4x4. I don,t like the way the turbo 400 and allison torque converter works. I think there is just to much slippage. I have seen as much as 500-600 rpm change when pulling hills with a camper and trailer in tow. also 200-300 rpm going into the wind. What I would like to do is install a sm465 and a 205 transfercase and still use the gearvendor. Has anyone used this transmission? Is it strong enough? I also think that going to a manual box will help the mileage a little more. any help would be appreciated

 

[Philip]

The sm465 would be very border line for a CTD. Look at using the NV4500 in its place. Better trans. It can be mated to a 205 with little issue. A NV5600 could be used also.



The 205 will hold up all right to a CTD. It was used in all the 1st gen trucks.



I can't say anything about hooking up a gear venders. Never had one.

 

[btanner]

I agree the sm465 would be very borderline for the cummins especially if you are considering bombing the truck. A nv4500 would be a good fit and a nv5600 would be even better. I thought about doing that when doing my conversion but I already had the 47r transmission so I decided to just use it until it blows up then I'll change to a nv5600. If you use a nv4500 plan on spending 3500 for all the parts and the transmission add a grand for the nv5600. The 13 inch clutch upgrade for the nv4500 would be an excellent upgrade especially if you are towing. You can do it for less but to do it right it will cost that much. The gearvender might need a different adapter but I think that you can buy them separately but you'll definately need to look into that. Best of luck



-ben

 

[pmartinez]

well I guess I will just keep the turbo 400 and use the 205 transfercase with the gear vendor. thanks

 

[DBCooper]

PMartinez, I have had trucks with the SM465 in them and they are very strong. I'm not a trans guy, but do know that they were used in trucks up to 2 1/2 tons. I would think that if a th400 can handle it, a sm465 could also. As far as a nv4500 being as strong? I seriously have my doubts. I'm not trying to argue with anyone, just looking at the facts that a 4500 is marginal for what we do with a 3/4 to 1 ton pickup. The 465 was used in much bigger trucks. I would post your question on pirate4x4.com and see what they say. Some of them are quite up on these things and as long as you can wade thru some of the childish comments on that site it has good info. Hope this helps.

Dan

 

[btanner]

I've seen a 465 blow up in a fj40 with 38s and stock landcruiser axles. Granted the guy wasn't very nice to the transmission and it may have been mounted crooked or something but I saw the case break. Maybe it was a freak accident but i saw it I haven't seen a nv4500 case break I know there are issues with the 5th gear but a lot of the vendors selling rebuilt nv4500 are now fixing the 5th gear nut and the problem is solved. The sm465 is also a 4 speed granted with the splitter it will be better. i actually asked a similar question about the th400 and I was told that there were several people who broke those using cummins. I think the thread is still on here somewhere in the conversions section. Those were guys that were towing heavy and had aux splitters. I guess in reality go with what you think will work best for you financially and for your application. Everything can fail with the right amount of abuse but there are several proven methods search around there are lots of options and usually people have done it before just have to search. Best of luck



-ben

 

[pmartinez]

Thanks for the replies guys. I do know the turbo 400 is a strong transmission. I just came back from a trip from Northern California to Central Oregon with a 4000 lb camper pulling a car trailer with a Jeep Cherokee, total weight about 17000 lbs. It worked very good and did not overheat. What I worry about on a SM 465 is the input shaft size and clutch disc. I remember a while back installing a dual disc clutch in a bread truck with a 4BT and T 19 trans. I don't remember who made it or where I got it. It was about 8 yrs ago and I don't have the truck any more. I have rebuilt some SM 465 transmissions none of them were broke just replaced bearings or synchronizers. But those transmissions were behind six cylinder and V 8 gas engines. I know the T 19 transmissions have a hard time with a 4 BT engine. I have changed at least 40 1st-2nd synchronizers in the last 8 years. I know the SM 465 is a good transmission but I question it behind the CTD .

 

[btanner]

here's that post I was talking about with the th400s



http://turbodieselregister.com/forums/showthread.php?threadid=93357&highlight=chevy

 

[T. Baker]

I run a Ranger overdrive and SM420 in mine. I had my engine bommed with no fuel plate and 370's etc. I finally ripped the hub out of a clutch. I put the fuel plate back in to limit torque. Most of the time you will be in 4th gear with a 4 speed so it is acting as a shaft and there is no load on anything. I would say the weak point is the input shaft size. The gears are really strong and none of them fall off like the NV4500. The NV4500 is good if you put a new main shaft and input shaft in it but that is alot of money. NV4500s stock are garbage from what I read on this site - unless you like gears falling off