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TH400 converter

dieselfuelonly

dieselfuelonly

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Location
Florence, AZ
Hi, wanted to see what is the best torque converter to buy as far as price and quality goes for a TH400 auto behind a 6.2 diesel? I know the stall speed has to be on the lower side and around the 1600-2000 rpm range for the diesel. Or should it be rated lower then that? Looking at a truck for sale that needs a converter but don't want to spend $250+ on one. Thanks.
 
There are a lot of good converters out there to choose from.

The TH400 converter is an easy one to get too, and not usually too hard on the checkbook.

The best converter for the diesel is one thats had all the blades welded in the pump and turbine. (internal components)

The low stall converters are the best for the 6.2/6.5.

Now when it comes to the rebuilts, I have seen a bunch of these over the years that have been rewelded with the drive hub and the crank pilots out of concentricity.
This results in a converter that wobbles and the entire assembly will vibrate like hell.

This eventually tears up the tranny and will often result in a broken crank, especially in a 6.2/6.5 engine.

Anymore, unless I know the rebuilders reputation, I will stick the converter in the lathe chuck and lightly snug up on the hub and then check to make sure the thing runs true.

Most reputable rebuilders check their finished product before they ship them out, but there are still a few outfits with sketchy quality control.

If you buy a "good used" converter, definately check the thing before stuffing it into a tranny.

Just some words of wisdom and hard knocks of the old road.

Missy
 
Spend the money for a Suncoast, you won't regret it. Depending on which convertor you have Some of them were not that good. The 3 bolt ones IIRC but I think the diesels only came with 6 bolts. You cannot go wrong with Suncoast.
 
FWIW the converter from my blazer was a 3 bolt, but that was a 700R4 not a TH400. I think the pickups is a 6 bolt though. Can't remember.
 
Suncoast has a good rep.

The diesels all came with 6 bolts.

Now YEARS ago, I had an 82 K5 with a 6.2 and the 700R went KABOOOOOOM all over the street.

I did not want to fool with it, so I replaced it with a TH350 and the converter had 3 bolts.
I ran that rig for a long time and never had even one issue.

The number of drive bolts is not so much the biggy here, but whats inside the converter.

You definately want a converter that has had the blades in the pump and the turbine welded/furnace brazed.

The blades on a normal gasser converter are simply slipped into the "torus" and then little tabs folded over and staked in.

A diesel tends to loosen all this stuff and as the blades wiggle loose, they churn up lots of metal particles.

If a blade does break loose, it tears the converter to shreds in very short order.

Missy
 
Hi, and thanks for all the info/knowledgable replies. Looking at a truck for sale that needs a converter and might try to see about getting one on Ebay as there were some decent deals from a few good sellers. Another question the truck is a 1982 K20. It's a 3/4 ton 4WD truck and would anybody know if it is guaranteed to have a Dana 60 front axle? I'm sure of the rear being a 14 bolt, but I'm not positive what axle it has in the front. I know the 5/4 ton CUCV pickups have the Dana 60 front axle, but given this is a regular 3/4 ton pickup I thought maybe there was a chance it was a Dana 44 (not built as heavy as the military unit). Thanks.
 
10 bolt. GM stopped using the Dana 44 late 70's. A K20 will NOT have a Dana 60. Only a K30(CUCVM1008/28) will have a 60 upfront. If your lucky enough to find an M1028 it has a detriot locker in the front axle as well as rear. The 10 bolt front ends were junk. Easily annilihated. 44's wern't bad. Reasonably strong and cheap and easy to repair but suffered from wheelbearing and ball joint issues if you run bigger than 33's. Not a big deal, just expect to change them often. I have seen spindle bolts break but that usually is a combination of big tires and kennyabuse....:rof: .BTW those can be drilled and replaced with larger bolts.
 
Meant to reply back sooner, but Ace wanted to thank you for the quick reply and straight forward facts on axles used in the trucks. It helped me out a lot and I ended up passing on the truck because of that 10 bolt front axle. My buddy and I are looking for an 82-87 GM truck for a pulling truck project, so anybody that knows of a good candidate let me know. What I've come to conclude is that a CUCV is by far the best choice for the truck we need just because of the Dana 60 front and 14 bolt rear. Bombproof combo and oh yea we're only looking for a 6.2 diesel truck too, because I'm not too big into "gas truck" pulling if you know what I mean. :thumbsup:
 
Then a CUCV is what you need...Try GL. PIA to deal with. Might want to stop by Steel Soldiers and check out the stickies on Buying from GL. Also may even find one in thier classifieds. Just bear in mind only the PU's had the heavy axles(M1008,1028) The Blazer (M1009) has the same whimpy 10 bolt junk the civvy models have. Worthless. If possible get a M1028. They had front and rear DL . M1008 only had rear locker.

On the TH350, Robyn, you are too kind to vehclies...:rof:
TH350's didn't hold up to weel for me either but I will be honest, those were my early 20's and I beat everything like a rented mule. The TH350 shifted very hard stock and the addition of a "shift kit" usually ended up in either a blown convertor(3 bolt) Cracked Flywheel(3bolt) or blew the sprage out (2nd gear IIRC). Had a trailer full of TH350 Carnage. If left alone and not beaten wasn't a bad tranny at all. even in race applications could be built well. Alot of aftermarket upgrades available like a hardened sprage. Seems the torque of big tires(I was running 44's with an LS6 powering it) was just too much though. Even cracked a case on one. Nope, TH400 still the standard.
 
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