What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

What fan and clutch for 350tbi

mrgoodwrench

mrgoodwrench

1/2 ton status
 Premium
Joined
Mar 8, 2015
Posts
244
Reaction score
123
Location
Minnesota
i have a 1990 suburban stock 350tbi. What fan and fan clutch would people reccamend. It has the stock clutch and 5 blade fan now. Truck is heavy on big tires runs an auto (for now) and gets used off road at low speeds in high heat at times. Just need to know if there is an upgraded clutch and fan i should use. If stock is good then thats fine too. I do want to keep mechanical though. Thanks for any info mike
 
mrgoodwrench said:
i have a 1990 suburban stock 350tbi. What fan and fan clutch would people reccamend. It has the stock clutch and 5 blade fan now. Truck is heavy on big tires runs an auto (for now) and gets used off road at low speeds in high heat at times. Just need to know if there is an upgraded clutch and fan i should use. If stock is good then thats fine too. I do want to keep mechanical though. Thanks for any info mike
Click to expand...
I would switch to a 7 blade fan and hd fan clutch.
For part numbers do a search there was a post going for a few weeks that discussed all the options. Something about overheating on the highway
 
imiceman44 said:
I would switch to a 7 blade fan and hd fan clutch.
For part numbers do a search there was a post going for a few weeks that discussed all the options. Something about overheating on the highway
Click to expand...

I did a search must have missed it i will look again thanks. Will the 7blade fan fit the stock shrouded ect... i will search for the thread you refrenced thanks mike
 
mrgoodwrench said:
Thanks
Click to expand...
I had seen that thread when searching and never saw much mechanical fan discussion so moved on. Then you refrenced it so i have now gone through and read all 8 pages and see no where they discuss fan blade or fan clutch part numbers. A flexfan is discussed and they mention having a hd clutch but thats all no part numbers and discussing a flex fan not factory style. Thanks for your help but i must be blind because i see nothing of use in that thread. Thanks mike
 
For my 77 I am ordering a Hayden 2797, severe duty. This is recommended for a 2.5" fan pitch, and up to 72 SQ inches of working surface, standard rotation.
I believe your 5 blade fan is 1.5" pitch, you need reverse rotation.
Slow speeds and heavy truck definitely would call for heavy duty or better. A fan with more surface area also.
 
Yea from what im seeing a hd or severe duty clutch is probably the way to go but as you said the hd and severe duty fan clutches all spec a 2.5 in fan pitch so i would need a new fan i have the 5 blade and i think its lower pitch. I guess im looking to see what fan blade and clutch will fit my application hopefully with the stock shroud and the fan in the right position in the shroud which i hear is about half the blade sticking out the back of the shroud. If anyone knows what clutch and fan blade will do this either by application (vehicle) or part number that would be great. And yes my truck is serp belt and drives water pump / fan with back side of belt / smooth side so i believe thats reverse rotation.
 
Yep 1500 was just looking for imput from someone who had maybe done it already thats all.
 
The motor and the rad will be in the same place, shroud may be different. Simple measurement will determine if your current shroud will work. Yes you do want the blade to sit halfway at should opening.
 
Cool i will get some measurements tonight and start googling blade and clutch options
 
mrgoodwrench said:
I had seen that thread when searching and never saw much mechanical fan discussion so moved on. Then you refrenced it so i have now gone through and read all 8 pages and see no where they discuss fan blade or fan clutch part numbers. A flexfan is discussed and they mention having a hd clutch but thats all no part numbers and discussing a flex fan not factory style. Thanks for your help but i must be blind because i see nothing of use in that thread. Thanks mike
Click to expand...
Sorry I have been reading a few on the same subject and might have confused threads.
I will check a few I can think of or tag the guys that were in the discussion.
 
ok so 393996 gm 7 blade fan should work for our trucks is spec'ed to 87 sbc, auto trans, hd cooling. The Hayden 2797 thermostatic severe duty fan clutch will work I just put one on my suburban. 2797 is same height as ac delco I took off. I have a 5 blade fan i thought it was more. If I find a less expensive fan I'll post it up. GM 393996 is @ $170.00.
 
yes they should be the same diameter I am going to measure the shroud right now
 
so my shroud is 21 1/4" across, afaik it is the original 1977 sb 400 shroud. I have @ 1 inch from the sides, only 1/4" from the top. didn't do th the bottom my 5 blade is 19+ inch across
 
You must log in or register to reply here.

Latest Posts

Top Bottom