I need higher gears!!

Hi all, first time jeep owner. And it happens to be a '67 CJ5. My dad's a fan and thought that I should be one too. I was "gifted" this jeep and am now discovering what I'm getting into. This jeep has a Chevy 350 small block freed from a '69 Camero. According to the old owner, its pushing 300 hp. Regardless of horsepower, it's pushing some low gears and I'd like to put in something higher so that I'm not popping the front wheels off the ground in first, or starting out in 4th. I'm not sure what the current ratio is (it's a Dana 44 and I'm guessing 5.38.) Any recommendations on some ratios?

Joshua G.

 

Yep. You're not the first to come here with a story like that.

The standard reply.
1) Keep the low (high numerically) gears. People pay big money to get those gears, and they are a great asset on the trail. Plus they work well with modern, taller tires.
2) Look into an overdrive. Cheaper, better, more flexible and will enhance the value of your jeep more than different axle ratios.
3) Modern engines are happy at between 2500 and 3500 RPM at highway speeds, so if you're in that range, you don't need different gears (tachometer!).
4) Jeeps are noisy: tire noise, gear noise, engine noise. The engine is probably working less than you think it is.

You need to be sure about your axle ratio. There will be a tag under one of the cover bolts, or if that's missing, the tooth count is stamped into the ring gear.

Welcome from Boston!

 

I dunno, 5.38 with a small block chevy? Thats a lot of gear. I think I am about the only one here that doesn't think the lower the gear the better. 5.38 with a small block almost isn't streetable. I drove a 48 cj2a with 5.38s and a 302. Just like you say, first gear ya pound it and the front tires come off the ground. Another problem with the spinning that SBC at highway speed it is going to get hot. Another issue with that kind of gear the teeth get pretty small.

I went to 3.73s in my 48 with the 302. I was happy with it. They are really easy to come by in the dana 44/dana 30. Everyone thinks they are worthless. I ran those gears with 33" tires in the 48. In my 74 I run 4.56 gears with 35" tires and in my 77 I run 4.27s with 33" tires both have V8s.

With that kind of horse power you might want to consider an axle upgrade rather than just changing gears. Drive it, wheel it, see what you break. If you have stock axles with that kind of power chances are they aren't going to last long anyway.

 

Hmm. 5.38s, 33s, 65 mph = 3560 RPM. With an overdrive, (0.75 final drive ratio) 2673. 3500 is ok, and 2600 is very comfortable. Those numbers go up as the tire diameter goes down. With a Dana 18 transfer case, the overdrive makes such good sense ... IMO.

I wouldn't advise going a lot faster either. Stability should be ok if all the systems are in good shape, but with big tires and lift, evasive maneuvers at that speed can require a lot of skill.

Good advice to drive it for a while though.

 

Joshua,

I'll trade you my 3.73 gears for whatever you got

If that's not an option, I'd say go spend the dough on an overdrive. Just keep it engaged, because it affects all gears... then you can have a Low, Medium and High range

 

Also, 4th gear was mentioned. With an SBC, am I to assume SM465? If so, adding an OD (cheaper than gears if you pay someone to set them up) would, in addition to what Tim and Sparky mentioned, have the added benefit of splitting the relatively large gap between 1st and 2nd while in low range.

 

For information on the overdrive check out Herm the overdrive guy's website.
http://www.hermtheoverdriveguy.com/
This guy is good with these, and very helpful, and will answer all your questions.
Plus his overdrives are cheaper than the Saturn ones by quite a bit and just as strong or stronger than they are.

Welcome to the ECJ5 site, by the way. :hurrican:

 

Not to mention the time your rig is down for the major surgery!

 

I got a stock 65 Cj5 F134 w/od (not good comparison but...) the overdrive to me is more valueable than the plow it came with. I'd have been very dissatisfied with the jeep with no od.
I just got back from a 30 some mile round trip to my father inlaws and maintained 50-55 mph the whole way. I'd listen to these guys and invest in the overdrive, on a 3 speed tranny with a granny low xfer case that gives me.....uhhh 16 different gears (I think, my math sucks )

 

Drove my 5.38 geared, 289 ford powered CJ2A for years with no OD ( the engine loved it) then I got the warn OD it gives you 16 speeds forward (4 spd) and four in rev. It now goes WAY to fast, at red line, for this type vehicle. It will give you, like was said, a lot of choices for different situations. I loved shifting into OD when backing up, saw a lot of head scratching!!!

Dale

 

Thanks for the help. I'm a newbie and still learning, just a 21 year old punk. I guess I found the right website. I'll check out the OD. I've only had the jeep for 8 days and it's been in the shop for 7.

Josh

 

Sparky, snot nosed and wet behind the ears might have come to mind 10 years ago, but not a punk.

 

Thought you might need a compliment tonight.R)