I have a 2003 Ranger Edge long wheelbase, 3.0
5 speed with the 8.8” axle with 4.10 gears. I kinda need some peer opinions on rear axle play, and I know surely my rear differential has seen better days. My current “issues” if you call it that, consist of: 1: Truck slightly jerks whenever gas pedal is pressed or depressed in any gear. When I drive normally it’s barely noticeable. Very noticeable in prolonged driving in 1st gear 2: When moving at idle in first gear, usually the whole truck will lurch slightly and eventually evens out after a while if ONLY at idle. It doesn’t do that anywhere above 1,000 rpm. 3: Truck sometimes “lunges” when given more throttle under a load usually in 4th/5th gear (going up a hill, towing a trailer, you get it). The first 2 issues I stated are nothing more than normal wear on the differential. This 3rd issue has me scratching my head though. I can’t really describe what it does, but it feels like the pinion gear skips teeth on the ring gear. The truck will jump once and a second later will jump again, and rarely it will jump a 3rd time. But after that if it’s under a constant load, it won’t jump.
I have driven the truck for about a year now and has had all 3 problems since I got it. It does have a good bit of play when you rock the driveshaft but it really doesn’t explain why it’s skipping teeth, if that’s what it’s doing. What’s really weird is, there’s no bearing noise or clunks from the rear axle at all. Does anyone know why it would be doing any of these things? Transmission is in good shape with very little slop in the gears.

 

Welcome to the forum

Pinion is not skipping teeth, so drop that idea

If rear axle is not making a LOUD howling noise when driving then its OK

I would lube the slip joint on drive shaft, it is inside the rubber boot
Or drop drive shaft and change U-joints and lube slip joint

As for the surging/lunging. I would clean the MAF sensor and the IAC Valve, and check throttle plate
Also replace PCV Valve(every 3rd oil change)

 

Sorry I didn’t clarify, the engine isn’t surging, it’s a small jump and it’s very obvious it’s coming from the axle. It only does it in 4th or 5th gear at lower rpms.

 

The slip joint in the driveshaft can cause that problem. It can bind or stick and make it feel like a jolt when it breaks loose. Lubing usually solves the problem. If you chose to ignore the advice given here that is your choice, but why ask in the first place?