1984 K5 Blazer with TH350NP203 conversion.

[AlanBrown]

Good day everyone,

I have some questions about a 1984 K5 Blazer that I picked up, which I am receiving a lot of mixed information from online. I recently purchased the vehicle and the previous owner had switched the original SM465 NP208 configuration for a TH350 NP203 set up. Now it is full-time 4WD with locking hubs (Only has 4Hi and 4Lo gears). I have seen numerous forums that people state not to go over 45mph on clear paved roads in 4Hi, but I am not sure if they mean with or without the hubs locked. Are there any speed limitations with this conversion driving in 4Hi and having the hubs free (not locked)? I frequently commute between 45-65 mph on clear roads, so I want to make sure that I am not causing abnormal wear.

Thank you for your time,
Alan

 

[Hogback Fabrication]

Does the 203 have a part time conversion kit or is it like factory with full time 4WD?

 

[AlanBrown]

Does the 203 have a part time conversion kit or is it like factory with full time 4WD?

I was told it is with the full- time 4WD. This is my first step into the 4x4 community, so apologies for the lack of knowledge. Is there a simple way to verify that it is?

 

[6872xtc]

I would test it by blocking the tires , put it in neutral with the engine off, then unlock the hubs, start it and see if it will move in gear.
If it won't, shut the engine off before you try to put it back in park.
Remember that the 203 originally has 5 shifter positions. 4 Hi, 4 Hi lock, neutral, 4 Low, and 4 Low lock.
When converted, you only have front wheels powered in the lock positions. The other positions become 2wd.
And those shifters can get hard to shift due to dirt and grease, so it may be difficult to determine if you have the lock positions.

 

[AlanBrown]

I would test it by blocking the tires , put it in neutral with the engine off, then unlock the hubs, start it and see if it will move in gear.
If it won't, shut the engine off before you try to put it back in park.
Remember that the 203 originally has 5 shifter positions. 4 Hi, 4 Hi lock, neutral, 4 Low, and 4 Low lock.
When converted, you only have front wheels powered in the lock positions. The other positions become 2wd.
And those shifters can get hard to shift due to dirt and grease, so it may be difficult to determine if you have the lock positions.

Thank you, it doesn't have the part time conversion kit.