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.

37 inch tires and 4:10 gears? (offroad use)

G

gmcjimmy88

1/2 ton status
Joined
Feb 10, 2005
Posts
559
Reaction score
2
Location
Fayetteville North Carolina
How bad is this going to be on the trails. I started a post a while aago but I think people thought I was asking about the road manners. This truck will rarely see the road. I will eventually go with 5:13's or 5:38's but cannot afford them now. Who does or have run this setup ON THE TRAILS? Any help would be great thanks. It is an 88 Gmc Jimmy 350 TBI and 700r4. Still running the 10 bolts as of now. I will upgrade my gears when I get better diffs.
 
It'll be a bit of a nuissance but won't be that bad. An aluminum transfer case with a nice low range does a pretty good job of hiding big tires and bad gears. I'm running 3.73s with 40s.
 
i had 4;56 with 37 just fine but i have the 203/205 if i needed low low

i am now runing 42tsl with the 4;56 am counting on the 203 205 to pull me threw ---- it will work out
 
You always need to take into account the overall low range ratio, just not what the axle gears are. With the 700r4 and, I assume, a 208 or 241 t-case you will have a pretty respectable crawl ratio for an auto (34:1). If you had a turbo 350 or 400 trans and an 205 t-case it would be a different story since 4.10's only net you an overall 20:1 ratio......even that combination with 5.13 axle gears is still a much higher 25:1.

I've ran 4.10's with 38's (700r4/241) on my low powered off-road toy for years and never really have any problems. My buddy runs the same tires and axle gears but with a C6/205 combo.....even with a lot more power he struggles on low speed crawling sometimes.
 
Did not think about that. I felt that the gearing was perfect with the 33's. I went down Daniele at Uwharrie in low/low range with my brakes out. Was really concerned but made it through. They were not all the way gone but was not even left to stop me with it in gear. By the way it was the worst part of Dan that I went down. Not a fun thing I want to try again.
 
I run 4.11's with 37" SSR's. TH350 and 241. It isn't too bad. I do have to use low for anything where you want the tires to spin LOL. It was a bit better with the 700R because 1st gear is lower, but it's a useable combination
 
Yeah, just back up and try again if you get a spot where you're causing a lot of slip in the torque converter. It'll help keep the trans alive and not overheated.

My 305TBI/465/208/3.73s with 40s wheels about as well as my 305carb/700R4/208/3.42s with 33s. Also about as well as a 6.2L/465/205/4.10 with 40s.
 
I'm runnin 38.5's and 4:10's w/out too many complaints... but I'm running a stroker w/ a high stall converter so the "oomph" is there for me.
 
I just did a trail run Saturday with 37s and 3.73's. I wasn't unhappy.

You can see pics here: China Wall That way you know I wasn't just running a dirt track. :D Mine is the yellow one.

I would like to go to 4.10s, but that is mainly for highway/mountain driving purposes.
 
I'm running...44's and 4.10's right now...
It's a little sluggist coming outta the hole...
but it's not bad...the 4.10 and 38's were better.

37's and 4.10's will work well for you. :thumb: :thumb:
 
Thank you all for the replies. I was really concerned about the issues I was going to have. From the sounds of it I will be ok if I ever get out of this country and get home to build my truck. THANKS TO EVERYONE WHO HELPED ANSWER MY QUESTIONS!!! If you all want to you can keep the replies coming. Thanks again
 
Last edited:
Don't worry about it. It will do fine. Just put a tranny cooler on the 700R4 to keep the setup cool as you offroad and you should be ok in the gear department.

Harley
 
JK5 said:
I'm running...44's and 4.10's right now...
It's a little sluggist coming outta the hole...
but it's not bad...the 4.10 and 38's were better.

37's and 4.10's will work well for you. :thumb: :thumb:
Click to expand...

I'm running 44's with 3.73's!!! The 5.13's are in the big box from ORD waiting to be installed. I'm really, REALLY glad to have the SM465. :thumb:
 
You'll torture your torque converter and tranny without lower gearing than 4.10. My tranny temps went thru the roof when wheelin on 37's and 4.10s before the doubler, even with the big 28000 B&M cooler and pusher fan. I got her up to 260* before I had to stop and let it cool back down. I wouldn't slap the bigger tires on until the gearing is better, however you do it, gearing wise. IMHO.
 
Ah yes Fred, but he has the poor man's doubler. 700R4/208. His low gear is much lower then your low gear was with a TH350/203. His temps will elivate some while crawling but not like yours did.

Harley
 
unless you can do it yourself, dont $pend the ca$h to regear half ton axles... just not worth it to pay someone else to do it. With the same amount of $ a place like 4wpw would charge you, you could go 1-ton.

j
 
Hossbaby50 said:
Ah yes Fred, but he has the poor man's doubler. 700R4/208. His low gear is much lower then your low gear was with a TH350/203. His temps will elivate some while crawling but not like yours did.

Harley
Click to expand...

Good point. :bow: I should have read the whole thread better... 6.2 said what the deal was.
 
Trust me Fred, I only notice because I am one of those "poor men" :D I wish I could afford cast ironitis but I make do with what I have and it works ok so I won't complain.

Harley
 
I do not plan on regearing the 10 bolts (unless I find a set cheap or free). I plan on getting 60's, 14blt, 12blt, whatever I can get cheaply and gearing them before putting them under the truck. My budget doesn't allow for much like most everyone here. I know in time I will get the diffs though. Thanks for all the input. I feel alot more comfortable about the stock gearing for now. Thanks again
 
You must log in or register to reply here.

Latest Posts

Top Bottom