Gear Change 4.56

xxdabroxx said:
Manual or auto, if auto does it have overdrive?
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This thread brings up some great points. I too, need to re gear to 4.56. I drive an 04 Rubicon with auto trans and 33s. I recently received a quote of $1,500 and one month out due to the shop being busy. Can someone provide a list of questions or parts to do this so I can ensure they would be doing everything they need to do at that price? Thanks in advance.
 
DC0046 said:
This thread brings up some great points. I too, need to re gear to 4.56. I drive an 04 Rubicon with auto trans and 33s. I recently received a quote of $1,500 and one month out due to the shop being busy. Can someone provide a list of questions or parts to do this so I can ensure they would be doing everything they need to do at that price? Thanks in advance.
Click to expand...

What is their warranty? 1) If they supply parts. 2) If you supply parts. Does it include labor if there is a failure?
Break in for gears. Are they going to do the initial run? If not, plan accordingly for the procedure to home from the shop.
Does the price include new axle seals? Or at least the labor if they are needed?
Is there an additional cost to put on new rotors and pads if necessary while they do the install. Should be NO additional labor IMO.
What is the cost of the parts, if they supply them, vs the labor?
What gear mfg?
What mfg bearing kits?
Will they be using the mfg recommended gear oil specs?

Just a few to get you started.

Allen
 
DC0046 said:
This thread brings up some great points. I too, need to re gear to 4.56. I drive an 04 Rubicon with auto trans and 33s. I recently received a quote of $1,500 and one month out due to the shop being busy. Can someone provide a list of questions or parts to do this so I can ensure they would be doing everything they need to do at that price? Thanks in advance.
Click to expand...
4.56 isn't enough gear for 33's with your particular automatic transmission. You have the 42RLE automatic which has a horrifically deep .69 Overdrive ratio that drops the engine rpms so much that with bigger tires, the engine will lug. Seriously, you'd be terribly frustrated with 4.56 and 33" tires. At a minimum, 4.88 is what you want with 5.13 actually being a choice more and more are running now with that particular transmission.

NO, neither 4.88 nor 5.13 will cause your engine rpms to be too high on the highway. On the contrary, those ratios will just get the highway rpms up to where they should be for that size of tire so the engine won't lug. Yes I know you see 4.56 commonly recommended for 33's but that is only when the transmission is the 5-speed manual transmission. Other transmissions might only need 4.10 for 33" tires but with your transmission, you absolutely want 4.88 or 5.13. Personally, and I have the same transmission as you, I'd go 5.13 for 33" tires.

Some clueless shop people, and trust me that not all are really up on the ratios different transmissions require, will try to convince you 4.56 is correct but they would be wrong, basing their opinion on experience with a different transmission or perhaps their V8 Chevy that would indeed run well with 4.56 and 33's.

Lastly, have the installing shop provide ALL of parts for the regearing. It may be possible to save a little $$$ by buying the parts yourself but then the shop wouldn't warranty the parts you provided, only their labor.
 
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Jerry Bransford said:
4.56 isn't enough gear for 33's with your particular automatic transmission. You have the 42RLE automatic which has a horrifically deep .69 Overdrive ratio that drops the engine rpms so much that with bigger tires, the engine will lug. Seriously, you'd be terribly frustrated with 4.56 and 33" tires. At a minimum, 4.88 is what you want with 5.13 actually being a choice more and more are running now with that particular transmission.

NO, neither 4.88 nor 5.13 will cause your engine rpms to be too high on the highway. On the contrary, those ratios will just get the highway rpms up to where they should be for that size of tire so the engine won't lug. Yes I know you see 4.56 commonly recommended for 33's but that is only when the transmission is the 5-speed manual transmission. Other transmissions might only need 4.10 for 33" tires but with your transmission, you absolutely want 4.88 or 5.13. Personally, and I have the same transmission as you, I'd go 5.13 for 33" tires.

Some clueless shop people, and trust me that not all are really up on the ratios different transmissions require, will try to convince you 4.56 is correct but they would be wrong, basing their opinion on experience with a different transmission or perhaps their V8 Chevy that would indeed run well with 4.56 and 33's.

Lastly, have the installing shop provide ALL of parts for the regearing. It may be possible to save a little $$$ by buying the parts yourself but then the shop wouldn't warranty the parts, only their labor.
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Thanks Jerry. You saved me from making a bad mistake!
 
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Oh! This is important. Make sure you test that the lockers and 4wd are actually working before you leave the shop. You would not want to get into a dispute over what happened after you left and went wheeling.
 
AOR said:
What is their warranty? 1) If they supply parts. 2) If you supply parts. Does it include labor if there is a failure?
Break in for gears. Are they going to do the initial run? If not, plan accordingly for the procedure to home from the shop.
Does the price include new axle seals? Or at least the labor if they are needed?
Is there an additional cost to put on new rotors and pads if necessary while they do the install. Should be NO additional labor IMO.
What is the cost of the parts, if they supply them, vs the labor?
What gear mfg?
What mfg bearing kits?
Will they be using the mfg recommended gear oil specs?

Just a few to get you started.

Allen
Click to expand...
Great comments. Thank you
 
One more thing, avoid those axle tube seals some clueless shops will try to push on you. They're not needed and indeed, can even hide a leaky inner seal. The axle tube "seal" the factory installed is all you want installed there. It's not really a seal so much as it is a barrier to keep the rocks, pebbles, etc. out of the axle tubes. If an inner axle tube seal fails, the factory outer tube seal will let that gear lube leak out so you know there's a seal problem that needs to be address... which thankfully doesn't happen very often.
 
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Jerry Bransford said:
4.56 isn't enough gear for 33's with your particular automatic transmission. You have the 42RLE automatic which has a horrifically deep .69 Overdrive ratio that drops the engine rpms so much that with bigger tires, the engine will lug. Seriously, you'd be terribly frustrated with 4.56 and 33" tires. At a minimum, 4.88 is what you want with 5.13 actually being a choice more and more are running now with that particular transmission.

NO, neither 4.88 nor 5.13 will cause your engine rpms to be too high on the highway. On the contrary, those ratios will just get the highway rpms up to where they should be for that size of tire so the engine won't lug. Yes I know you see 4.56 commonly recommended for 33's but that is only when the transmission is the 5-speed manual transmission. Other transmissions might only need 4.10 for 33" tires but with your transmission, you absolutely want 4.88 or 5.13. Personally, and I have the same transmission as you, I'd go 5.13 for 33" tires.

Some clueless shop people, and trust me that not all are really up on the ratios different transmissions require, will try to convince you 4.56 is correct but they would be wrong, basing their opinion on experience with a different transmission or perhaps their V8 Chevy that would indeed run well with 4.56 and 33's.

Lastly, have the installing shop provide ALL of parts for the regearing. It may be possible to save a little $$$ by buying the parts yourself but then the shop wouldn't warranty the parts you provided, only their labor.
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Just to add to Jerry's great reply...

B926DCC8-CADB-4DEF-BE05-8615136A62C1_zpszqnqhebi.jpg


My jeep is an '05 with the 42rle. I'm running 33's and geared to 5.13.

Should have done it years ago.
 
Keston Shook said:
Thanks that really helped!! So if the jeep did have over drive the gears would be different then? This is just for my curiosity at this point lol
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Those rpms in his photo are exactly what you want to see at that speed and those are the rpms you would see with 5.13 on the highway with 33's. Perfect rpms and as you can see, they're not even close to being too high.
 
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I am also going to regear. I have a 99 with 4.0 and the 32RH three speed auto. I am going to move up to 35's. I see so many different recommendations. I think 4.56 gears are what I will need. Am I correct?
 
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