Transfer case problems

[no_3of4]

Hello all, I am new to this but I have a 86 k-5 blazer. It has a np 208 in it and 78 350. I dont know much about the transfer case part of the vehicle. But when in 2 wheel it runs fine but if i engage 4hi and lock the hubs it pops under the body, sounds like the case, but not sure. In 4 lo it really make a noise w/o even engaging the hubs. Any thoughts would be appreciated. Thanks..
no_3of4

 

[randy88k5]

Is the truck moving while you shift, or do you shift at a complete stop?

Does the noise only happen when you turn hard?

 

[no_3of4]

I am at a complete stop when i change. It is is smooth switching between 2 and 4 but when in 4 wheel it makes noise. If i am in 4 hi and try to climb it gets worse. almost like the chain is slipping? I dont know if there is a linkage adjustment that may be out? but as far as turning it is fine.

 

[Chaddy]

I bet your chain is slipping....Time to open the case and rebuild

 

[colbystephens]

as a quick check before you pull the case, make sure you check your u-joints. probably not the issue... but just in case. it's a lot cheaper/easier! i don't remember if the driveshaft for the front axle has a ujoint at the t-case - if it does, that'd be the first place i'd check.

 

[diesel4me]

check the ratios of both axles..

It might be your truck had an axle swapped in that does not have the same gear ratio as the other,that will cause binding and something has to "give",usually a hub releases with a loud bang,or the transfer case chain might jump over the sprockets if its loose enough..if the truck feels like its binding in 4wd,this is a very good possibility..I had a 71 K5 I bought that had a 3.08 rear axle, and a 3.73 front!--needless to say it was useless in 4wd!

Also ensure all 4 tires are the same size--MEASURE them with a tape measure around their circumfrence,don't just assume they are all the same just because the sizes printed on the tires match--I've seen many tires of different brands LABELED as "235/75/15,for example--but when you measure them,one brand will be up to 2" in diameter different than another brand!..