Camshaft bearings wT or woT ?

[44zoomer]

Hello I'm rebuilding 2001 gmc 4.3 and the camshaft bearing has two oil holes in front and bane bearings. Plus the front has a notch in it.
When ordering bearing for this motor, it says with T on front of the block or without T in front of the block. I find no T anywhere on my block but seen some pictures and it look like the T on block is the one with two oil holes.
Anyone know?

[chevymaher]

There are 2 plants making these engines. Tonawanda is the T. In my year they used different machining processes and parts did not interchange. Which is why it would be important.

On mine it is on the passenger side front of the block. There is a stamp on the block right under the head. Behind the alt bracket. It is a factory assembly record. But a T is part of the number sequence.

[Speedsmile]

I can confirm the information above it's the difference between the Tonawanda or Romulus plants:
The distinction is made because the camshaft bearing outer diameters are different for the T and non T engines. If you take the wrong set, one cam bearing may be loose or one might be difficult to get in, and get tight (see below). You have to find the casting number of the block. The crank casting number may also help in identifying your engine.

According to my notes (please double check with info on the net):

Camshaft bearing outer diameter:
Bearing number 1-4 in increasing number:
wo/T [inches]
1: 2.02
2: 2.01
3: 2.00
4: 2.01

T [inches]
1: 2.02
2: 2.00
3: 2.01
4: 2.02


So be sure you have the right set....

[44zoomer]

I cant locate the number. Do you see it?
Top pic has a 4G on the left
Bottom pic has numbers1469909

[44zoomer]

Is this it?
This is on the back of the block

[WoodButcher]

TMI for me...
Here are a handful of links I had saved, careful though as one or more may have been written before '01. The first one was.
http://www.enginebuildermag.com/2000/04 ... chevy-262/
http://www.kohlerpower.com/onlinecatalog/pdf/tp6103.pdf
http://www.chevy-wiki.com/wiki/GM_Vortec_engine
http://www.hotsixes.com/chevy-v6/5/
http://www.crankshaftcoalition.com/wiki ... ee_engines

[44zoomer]

Great...Thanks for the info. All I have to do is look and the front and back bearings and see if they are the bigger ones. If so Than its a T motor.
Thanks my friend.

[WoodButcher]

Welcome, the pic you have of the rear of the block shows the raised circle of dots like a clock and the lack of a "T" anywhere made me think Romulus but the fact is I'm no wrench and have never rebuilt an engine. Any thoughts I have on the matter are just tidbits of trivia caught in my gray matter while trolling the interwebs.
I hope in those pages you were able to locate a definitive answer.

[paulo57509]

Unless the block has been decked, I think the "T" engine code prefix should be stamped on the pad shown.



Edit:

From the Crankshaft Coalition link:

MORE ABOUT BLOCKS

There is one other subtle difference in the blocks. The cam bearing sets are different, depending on whether the block was made in Romulus or Tonawanda. The Tonawanda blocks use two larger diameter cam bearings, one in front and one in back, instead of only one large one in the front. Both bearing sets are available in the aftermarket.

There are three characteristics of each block which will tell you where it was manufactured:

If it’s a Tonwanda engine, it will have a "T" stamped on the machined surface on the block just in front of the right cylinder head. The engine ID will be number stamped on the pad, and the chamfer on the cylinders will be quite shallow;
If it’s a Romulus engine, it will have an "R" stamped on the machined surface on the block. The ID number will be made up of a series of dots, and the cylinders will have a deep chamfer on them.

Some of the blocks are drilled for a knock sensor and some aren’t. It’s almost impossible to know which applications came with and without the sensor hole, so most rebuilders drill and tap every block so the hole is there when it’s needed.

[44zoomer]

Thank you. I will remove the paint in that area and check. Whats strange is I bought two bearing sets. 1 for the T and the other without the T.
Bearing size were all the same except the T had two holes in front and back bearing.